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Fetal Alcohol Syndrome (FAS) occurs in approximately 3 of 1,000 live births in the general population of the U.S. and is the leading known cause of mental retardation. The Midwest Regional Fetal Alcohol Syndrome Training Center (MRFASTC) surveyed 1,000 licensed occupational therapists (OT) of the American Occupational Therapists Association in a six-state Midwest region, including Missouri, Iowa, Nebraska, Kansas, Oklahoma, and Arkansas to assess knowledge and attitudes regarding FAS. Nearly 20% of the OTs responded. Of the respondents, nearly 94% regarded at least 1 drink per day as being 'heavy' in a pregnant woman. There was an increase in the number of respondents who thought it was acceptable to consume 1 drink or more with each advancing trimester of pregnancy. 92% of the OTs indicated a willingness to counsel a mother of a child having FAS, but 96% indicated a poor to fair ability to select valid and reliable assessment instruments for screening a child for FAS. Only 6% of the OT respondents indicated a good-excellent ability to conduct brief interventions on alcohol cessation for women. The data collectively indicate OTs possess similarities to other health care providers, including physicians and psychologists, in the misunderstanding or deficits of knowledge and skills associated with FAS and that they are largely unprepared to provide intervention for women 'at risk' for FAS, or to recognize correctly FAS in children. There is a demonstrated need, and desire, by the practicing OTs for continued education related to alcohol abuse associated with FAS.

Increase in oxidative stress after chronic ethanol consumption can result in hepatic injury. Because polyphenolic compounds can offer antioxidant protection to the cardiovascular system, this study was designed to investigate whether dietary supplementation of polyphenols from grapes may ameliorate hepatic injury resulting from chronic ethanol consumption. Male Sprague-Dawley rats were administered the following diets for 2 mo: 1) Lieber-DeCarli (L-D) diet with isocaloric amount of maltose instead of ethanol (Basal), 2) the L-D diet with 50g/L ethanol (EtOH); 3) L-D diet with 50 mg/L of grape polyphenols (GP) and 4) ethanol diet with GP (EtOH + GP). Rats given EtOH or EtOH + GP diets had significantly more hepatic triacylglycerols (P < 0.0001) and lipid peroxidation products (P < 0.01) compared with those given the Basal and GP diets. In addition, ethanol ingestion also decreased significantly (P < 0.01) the proportion of 16:0 and increased 18:0 and 18:1 in hepatic phospholipids, suggesting a perturbation of the de novo fatty acid biosynthesis pathways. However, GP supplementation alone and GP added to the ethanol diet did not alter the lipid changes mediated by ethanol except for the levels of 22:6(n-3) which were significantly (P < 0.05) higher in the EtOH + GP group than in the EtOH group. Despite a lack of gross lipid changes, histologic assessment showed significantly (P < 0.05) less hepatic damage in the GP + EtOH group compared with the EtOH group. These results clearly distinguished ethanol-mediated changes in hepatic morphology from the changes in hepatic lipids and further demonstrated the ability of GP to ameliorate hepatic damage resulting from chronic ethanol consumption.

The hypothalamic-pituitary-thyroid (HPT) axis functions abnormally in man and animals chronically exposed to ethanol. The most consistent observation in humans is that the thyrotropin response to thyrotropin-releasing hormone (TRH) is blunted. We have tested the hypothesis that chronic ethanol treatment in rats leads to a diminished responsiveness of the hypothalamus to central stimulation. Animals were maintained on 1 of 3 diets for 4 weeks: (1) laboratory chow and water provided ad libitum (chow-fed), (2) Sustacal chocolate liquid diet with vitamin mixture containing 5% (w/v) ethanol provided ad libitum (ethanol), or (3) Sustacal chocolate liquid diet with vitamin mixture containing sucrose substituted isocalorically (35%) for ethanol and provided in amounts matched to a weight-paired, ethanol-treated animal (pair-fed). At the end of 4 weeks, the animals were evaluated for their response to a single injection of ethanol (3 g/kg, ip) and/or exposure to 5 degrees C. Chronic ethanol treatment produced an increase in TRH mRNA in neurons of the paraventricular nucleus and fully blocked the thyrotropic response to cold exposure. However, chronic ethanol-treated animals did not exhibit altered basal levels of triiodothyronine or thyrotropin, nor did they have an altered response to a single injection of ethanol. These data demonstrate that chronic alcohol exposure alters functioning of the hypothalamic-pituitary-thyroid axis at least in part by affecting TRH neurons of the paraventricular nucleus.

F1 hybrid New Zealand Black (NZB) x New Zealand White (NZW) (NZB/W) mice are hormone-sensitive models of the human disease systemic lupus erythematosus. In this study, NZB/W fetuses produced by pregnant NZB mice were compared with F1 C57BL/6 x DBA/2 (C57/DBA2) hybrid fetuses produced by nonautoimmune C57BL/6 females. Dams of both strains were treated with testosterone or the androgen blocker flutamide to alter the hormonal environment in late gestation. Hormonal changes in male fetuses carried by treated dams were of interest because hormonal manipulation using either testosterone or flutamide has been shown to increase longevity in male NZB/W offspring. Testosterone-implanted NZB dams developed the expected elevations in circulating maternal testosterone, whereas C57BL/6 dams treated with either testosterone or flutamide had elevated maternal serum testosterone concentrations. The treatment-induced changes in circulating testosterone in NZB dams and C57BL/6 dams were not reflected in serum from 18-day NZB/W or C57/DBA2 fetuses. Male NZB/W offspring from untreated control NZB dams had unexpectedly high levels of serum estradiol and alpha fetoprotein and relatively low extractable testicular testosterone, compared with nonautoimmune male control fetuses. Maternal testosterone treatments produced a significant decrease in serum estradiol in NZB/W male fetuses, and placental testosterone content was also reduced. Our findings suggest that placental androgen control is regulated differently in the autoimmune NZB-NZB/W vs. the nonautoimmune C57BL/6-C57/DBA2 maternal-placental-fetal unit.

Ethanol exposure during critical periods of development results in alterations of central nervous system morphology and function. In this study, the effects of acute ethanol exposure on the number of neurons expressing luteinizing hormone-releasing hormone (LHRH) messenger RNA (mRNA) has been analyzed. Also, the expression of LHRH mRNA in the diagonal band of Broca/preoptic area (DBB/POA) was determined. Pregnant C57BL/6J mice were intubated with two doses of a 25% solution of ethanol or water (2.9 g/kg body weight) 4 hr apart on gestation day 7 (G7), G10, or G11. Animals were killed on G18, and in situ hybridization was utilized to detect neurons expressing LHRH mRNA. The number of neurons expressing LHRH mRNA was determined along their migration route from the rostrum into the forebrain. Ethanol exposure on G7 did not significantly change the number of neurons expressing LHRH mRNA on G18 compared with that in control animals. However, the number of neurons expressing LHRH mRNA in the nasal septum area in animals exposed to ethanol on G10 or G11 was significantly less than the number in control animals (p < 0.05). Prenatal ethanol exposure on any of the aforementioned treatment days did not alter the expression of LHRH mRNA at the level of the DBB/POA on G18 in ethanol-treated animals compared with control animals. Also, neuron-specific enolase mRNA expression at the level of the DBB/POA was not altered by prenatal ethanol exposure. Therefore, ethanol exposure on the aforementioned treatment days did not differentially affect LHRH mRNA expression compared with neuron-specific enolase mRNA expression at the level of the DBB/POA.(ABSTRACT TRUNCATED AT 250 WORDS)

A single dose of ethanol increases cellular levels of the mRNA encoding thyrotropin-releasing hormone (TRH) in neurons of the paraventricular nucleus (PVN), but blocks the cold-induced increase in the levels of this mRNA. Because the thyrotropic response to cold is dependent upon TRH secretion, we hypothesized that ethanol uncouples the stimulus-induced regulation of TRH secretion from the stimulus-induced regulation of TRH expression. We employed two complementary strategies to test this hypothesis. The first was to determine whether ethanol alters pituitary sensitivity to TRH. Animals given a single intraperitoneal injection of ethanol (3 g/kg) that produced a blood alcohol concentration of nearly 300 mg/100 mL exhibited the same increase in circulating levels of TSH following an intravenous infusion of TRH. Thus, ethanol does not appear to alter pituitary sensitivity to TRH. Second, we tested whether ethanol blocks the cold induction of c-fos expression in TRH neurons of the PVN. Both cold exposure and ethanol induced the expression of c-fos in the PVN and in TRH neurons; the effects of cold and ethanol on c-fos expression were additive. Thus, ethanol clearly does not block the cold activation of TRH neurons.

Previous studies have shown that fetal ethanol exposure (FEE) may have long-term effects on the function of catecholaminergic neurons in different regions of the CNS. The present study is the first to examine the effects of FEE on regional brain catecholamine responses following acute stress (a single 60-min restraint stress), repeated stress (single periods of restraint stress on 1, 5, or 10 consecutive days), and recovery from stress (recovery for up to 60 min in the home cage following a single 60-min period of restraint stress). Both male and female offspring from FEE, pair-fed (PF), and ad libitum-fed control (C) groups were tested in adulthood to determine catecholamine content in the cortex, hypothalamus, and hippocampus. A single period of restraint reduced cortical norepinephrine (NE) content in FEE and PF animals compared with that in the cortex of C animals, and reduced hypothalamic NE content in FEE female offspring below that found in animals in all other groups. In contrast, hippocampal NE content was higher in FEE than in C animals following a single period of restraint; PF animals had intermediate levels of hippocampal NE and did not differ significantly from either FEE or C animals. Following repeated periods of restraint, cortical NE content was lower in FEE than in C animals; PF animals once again had intermediate levels of NE. Importantly, basal (nonstressed) NE content did not differ among groups in any brain area examined. In addition, several significant changes in regional brain catecholaminergic responses to acute stress were observed in animals across all treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of a single intraperitoneal injection of ethanol (3 g/kg b.wt.) on the hypothalamic-pituitary-thyroid system was explored as a possible explanation of the hypothermic effect of ethanol. Serum thyroid hormones were significantly reduced by ethanol injection, but ethanol did not affect the cold-induced increase in serum thyroid hormones or thyroid-stimulating hormone (TSH). Since cold-exposure stimulates serum levels of TSH and thyroid hormones by stimulating thyroid-releasing hormone (TRH) release from neurons of the PVN, these findings demonstrate that ethanol did not block pituitary response to TRH or thyroid response to TSH. Paradoxically, ethanol increased cellular levels of TRH mRNA in the paraventricular nucleus (PVN), and blocked the cold-induced increase in TRH mRNA, suggesting that ethanol uncouples the regulation of TRH gene expression from the regulation of TRH release specifically in neurons of the PVN. Measurements of the effects of ethanol on TRH mRNA in thalamus, and beta-actin, vasopressin, somatostatin and corticotropin-releasing hormone (CRH) mRNAs in the PVN in addition to TRH mRNA revealed very specific effects of ethanol on the TRH neuronal system.

Prenatal ethanol exposure has been shown to result in craniofacial malformations as well as alterations of central nervous system morphology and function. Previous studies have demonstrated that acute ethanol exposure on gestational day 7 in the developing C57BL/6J mouse resulted in craniofacial abnormalities similar to that of children with fetal alcohol syndrome. We investigated the effect of ethanol on the migration and number of immunoreactive LHRH (irLHRH) neurons in this strain of mouse. Pregnant mice were intubated with 2 doses of a 25% solution of ethanol 4 h apart on gestational day 7 (G7). Control animals were intubated with water. Animals were sacrificed on G14 or G18 and immunocytochemistry was used to identify irLHRH neurons that were visualized by light microscopy. Fetal ethanol administration did not substantially affect the migration of the LHRH neurons from the medial nasal placode into the forebrain on G14 or G18. The total number of irLHRH neurons was not significantly different on G14 in ethanol-exposed animals as compared to the number in control animals. However, the total number of irLHRH neurons on G18 was significantly less (P less than 0.03) in 4 neuroanatomical regions in fetal ethanol-exposed mice compared to those in control mice; the nasal septum, the traverse area superior to the cribriform plate and ventromedial to the olfactory bulbs, the arch area which included the olfactory tubercle, medial septal nuclei and anterior hypothalamus in G18 fetuses, and preoptic area of the brain. Coronal investigation of the number of irLHRH neurons on G18 indicates that the loss of irLHRH neurons occurred predominantly in the medial region of the rostrum and brain.

Fetal alcohol exposure (FAE) is associated with a variety of physiological and behavioral dysfunctions. Effects of FAE on reproduction have been described that include delayed puberty, altered gonadotrophin secretion and steroidogenesis, and altered sexual behavior. Earlier work suggested that pituitary function was compromised in adult fetal alcohol-exposed female rats. This study examined the effects of LHRH and PMA in vitro on LH beta-mRNA expression in pituitary fragments from FAE animals; a separate experiment examined the effects of estradiol-17 beta on LH beta-mRNA under similar conditions. The results indicate that the pituitary glands of FAE females have a reduced ability to respond to these three stimuli. The reason for this reduced responsiveness to LHRH, PMA, and estradiol-17 beta is not clear, but the alterations suggest that LH synthesis is impeded following fetal ethanol exposure.

Adult male hamsters were maintained under 14 hours of light per day and randomly assigned to groups that received daily afternoon melatonin (25 micrograms) or vehicle injections. Animals from both groups were killed following 4, 8, and 12 weeks of treatment. By 12 weeks, the melatonin-treated hamsters had significant reductions in the weights of the testes and seminal vesicles, serum testosterone levels, and activities did not differ between groups. In a second experiment, hamsters were hypothalamic-preoptic area (HPOA) aromatase activities. Hypothalamic-preoptic area 5 alpha-reductase activities did not differ between groups. In a second experiment, hamsters were again treated with melatonin or vehicle for 12 weeks prior to being killed. After 10 weeks of treatment, groups of melatonin-treated animals received subcutaneous silastic capsules (5, 10, or 20 mm) filled with testosterone. Animals in two other groups were given blank implants or no implants at all. Two weeks later, at autopsy, reproductive organ weights, serum testosterone levels, and HPOA aromatase activities were significantly suppressed by melatonin administration. 5 alpha-Reductase activity in the HPOA was not affected. Hamsters that had been given the 10- and 20-mm testosterone implants exhibited normal seminal vesicle weights and HPOA aromatase activities. These results suggest that melatonin-induced reduction of HPOA aromatase activity is mediated by decreased circulating levels of testosterone.

Fetal alcohol exposure (FAE) is associated with a variety of physiological and behavioral dysfunctions, including deficits to reproductive function. FAE has also been shown to increase brain beta-endorphin levels. This study sought to determine whether the common delay of the onset of puberty in fetal alcohol-exposed animals could be due to increased opiate inhibition of LH release. Prepubertal female rats were injected with an opiate antagonist, naltrexone, over days 26-29. This naltrexone treatment led to an acceleration of vaginal opening and first estrus in FAE animals; had no effect on chow-fed or pair-fed controls. The vaginal opening and first estrus advancement in FAE animals occurred at a lower body weight indicating independence from growth-promoting effects of the drug treatment. It is concluded that delays in puberty in FAE animals are not directly due to pituitary pathology, but are related, at least in part, to increased inhibition of the LHRH neuron and functional impairment of gonadotrophin secretion.

Endocrine feedback of testosterone (T) in regulation of the hypothalamus is via the effects of T on the noradrenergic system. The current experiment was performed to determine the effects of fetal ethanol exposure (FEE) on the norepinephrine (NE) and dopamine (DA) content in the hypothalamic-preoptic area (HPOA) of adult male rats, and the response of NE and DA to T administration. Pregnant rats were exposed to diets containing either a liquid diet containing ethanol, a liquid diet containing sucrose isocalorically substituted for ethanol, or a chow and water diet. Male offspring were castrated or sham-operated at 45 days of age. The animals received either testosterone propionate (TP) or an oil vehicle. HPOA was collected at 55 days of age from each animal and NE and DA content was measured by HPLC-EC. There was no significant alteration of NE or DA content in the HPOA in FEE animals compared to catecholamine levels in animals derived from dams on the control diets. Castration had no significant effect on NE and DA content in the chow-fed or pair-fed animals. TP administration significantly reduced NE content only in the chow- and pair-fed animals but not in the FEE animals. DA content in the HPOA was not affected by castration, but TP administration also resulted in significantly reducing DA content in chow- and pair-fed castrate male rats but not in FEE castrate male rats. The results indicate that FEE alters the response of the noradrenergic and dopaminergic neurons in the HPOA to T administration.(ABSTRACT TRUNCATED AT 250 WORDS)

We have previously reported detrimental effects of in utero ethanol exposure on testicular steroidogenic enzyme activity in newborn rats. It is now reported that in utero ethanol exposure during Day 12 of gestation through birth has no apparent morphological effect on the testes of Day 1 neonatal rats. It appears that the detrimental effects of ethanol on testicular steroidogenesis can be manifested at the biochemical level in the absence of morphological effects. However, it remained unknown as to whether acute exposure to ethanol would elicit similar biochemical effects as chronic ethanol exposure on testicular steroidogenesis. To test this possibility ethanol was injected at 0, 1, or 2 g/kg intraperitoneally (IP) into rats of various postnatal ages. Plasma ethanol and testosterone levels as well as testicular 17 alpha-hydroxylase and C17,20-lyase activities were measured. The results indicate that acute exposure to ethanol significantly (p less than 0.05) inhibits the catalytic activity of testicular 17 alpha-hydroxylase in the newborn rat testis. This inhibition was specific since the activity of testicular C17,20-lyase was not affected. In conjunction with the reduction in testicular enzyme activity, plasma testosterone levels were reduced to 30% of the control levels in newborn animals receiving ethanol. In older animals, i.e., postnatal Day 20 and 40 rats, plasma testosterone levels were reduced, but not significantly, following ethanol treatment. Furthermore, testicular enzyme activity was not significantly reduced following ethanol treatment in these same older animals. These results suggest that the newborn rat testis is especially sensitive to the effects of ethanol.

The ontogeny of chick pineal serotonin N-acetyltransferase (NAT) activity was investigated in explanted chick pineal glands at 4, 10 and 21 d of age. Nocturnal levels of the enzyme and the response of the enzyme to light exposure were determined in pineal glands maintained in short-term culture at each age. The results indicate that nocturnal NAT activity was increased in the glands from older birds. Nocturnal levels of NAT activity at the time of the initiation of the experiment were threefold greater in glands from 21-d-old birds as compared to that in glands from 4-day-old chicks. The response to light was similar in all three ages examined; light induced a significant decrease in NAT activity within 60 min in explanted glands from 4-d-old chicks and within 180 min in the glands from the 10- and 21-d-old chicks. A paradoxical transient increase in enzyme activity occurred immediately (within 5 min) following light exposure which was significant in the glands from the youngest chicks, and present, but more variable, in the older chicks. These data indicate that the nocturnal enzyme activity is greater in glands from older birds, but that light exposure of explanted glands initiates a transient rise followed by a decrease in NAT activity at all three ages.

The local formation of the testosterone metabolites 5 alpha-dihydrotestosterone and 17 beta-estradiol within the hypothalamic-preoptic area (HPOA) is essential for the normal sexual differentiation of the male central nervous system (CNS) during a perinatal critical period in the rat. Testosterone, the substrate for these reactions, is derived primarily from synthesis within the fetal testis. Fetal alcohol exposure (FAE) during this critical period profoundly affects fetal testicular steroidogenesis as well as the sexual differentiation of the CNS. The present study was conducted to determine whether FAE directly affects the local metabolism of androgens within the developing CNS or whether reduced androgen substrate, via a testicular lesion, is a more likely explanation for the known effects of FAE on the CNS. The enzymatic activities of 5 alpha-reductase and aromatase were simultaneously quantitated in the newborn rat HPOA following FAE. Neither the enzymatic activity of 5 alpha-reductase, aromatase nor their ratio were significantly influenced (P greater than 0.05) by FAE with respect to controls. FAE apparently does not alter the disposition of the androgens within the newborn rat HPOA. These results support the hypothesis that FAE alters the sexual differentiation of the CNS through inhibition of androgen biosynthesis at the level of the perinatal rat testis.

Pineal serotonin N-acetyltransferase (NAT) is the enzyme that catalyzes the production of N-acetylserotonin from serotonin and is the rate limiting step in the biosynthesis of melatonin in the chick pineal gland. Chick pineal NAT activity is decreased by light and by noradrenergic agents that act at the alpha-2-adrenergic receptor. Light-induced inhibition of nocturnal NAT activity can be demonstrated by exposing 4-day-old chicks to light, or by exposing pineal gland explants cultured in vitro either to light or to UK 14,304 (an alpha-2-adrenergic agonist). The inhibition by either light or UK 14,304 is preceded by a transient, but consistent rise in NAT activity. The paradoxical, transient light-induced rise in enzyme activity is mimicked by UK 14,304 which suggests a similarity in mechanisms of light and adrenergic signal transduction associated with the regulation of NAT activity.

Adult male albino rats were acclimated to constant light (light:dark-LD-24:0) or to darkness interrupted with brief periods of light at 6 h intervals (LD 1/4:5 3/4 X 4) concurrently with rats maintained in a LD 14:10 photoperiodic cycle. The activity and rhythmicity of pineal serotonin N-acetyltransferase (NAT) was examined at regular intervals for 24 hours in rats maintained in the experimental photoperiods and compared to pineal NAT activity and rhythmicity in rats maintained in the LD 14:10 photoperiod. The results indicate that constant light is capable of depressing nocturnal levels of rat pineal NAT and obliterating the pineal NAT rhythm. Likewise, rats subjected to darkness interrupted with brief periods of light at 6 h intervals experienced a similar response in pineal NAT activity to animals subjected to constant light, i.e., pineal NAT activity was persistently low and the rhythmicity was obliterated. The results are discussed relative to the hypothesis that the pineal NAT activity responds to an endogenous rhythm in photoperiodic time measurement. The evidence herein suggests that the time of occurrence of environmental light in the photoperiod is more important in determining pineal NAT activity and/or rhythmicity than is the total amount of darkness or the dark to light ratio to which animals may be subjected.

Exposure of adult male hamsters to light-dark (LD) cycles of 0:24 (in hours) for 12 weeks induced atrophy of the testes and accessory sex organs and a drop in immunoreactive pituitary and plasma prolactin levels. The subsequent exposure of these hamsters to LD 14:10 cycles caused regeneration of the sexual organs and an increase in pituitary LH and prolactin levels. Likewise, the weekly treatment of dark-exposed hamsters with subcutaneous melatonin-beeswax pellets led to regeneration of the peripheral reproductive organs and an increase in pituitary LH and prolactin levels. After gonadal regeneration, complete darkness failed to induce atrophy of the reproductive system indicating that either long photoperiods or melatonin treatment cause the pituitary-gonadal axis to be refractory to the inhibitory influence of darkness.

Several drugs have been shown to cross the placental barrier and affect the fetal testis causing a reduction in testosterone with a resultant impairment of sexual differentiation and an ultimate problem in adult sexual function. In this study, pregnant female rats were treated with 25 mg/kg of the pesticide 1,2-dibromo-3-chloropropane (DBCP). Treatment began on Days 14.5, 16.5, or 18.5 and continued through Day 19.5 of gestation. Some animals were killed on Day 20.5 of intrauterine life and fetal intratesticular testosterone was measured. All other animals were allowed to deliver, and the males were raised to adulthood. At adulthood, body, testis, prostate glands and seminal vesicle weights were recorded. Intratesticular testosterone and luteinizing hormone (LH) receptors were measured. Male and female sexual behavior was quantified and the volume of the sexually dimorphic nucleus of the preoptic area of the hypothalamus was calculated. The histological appearance of the testis was also examined. Treatment for 6 days during fetal life with DBCP decreased intratesticular testosterone by 50% compared to controls at 20.5 days of gestation. At adulthood, all male rats treated during fetal life had a reduced body weight that was correlated with the duration of exposure. Adult testis weight was reduced to 75% of controls as a result of 2 days of fetal exposure to DBCP, whereas 4 and 6 days of exposure during fetal life reduced testis weight by greater than 90%. LH receptors and intratesticular testosterone, in the adults treated during fetal life, were also dramatically reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

The daily s.c injection of 25 microgram melatonin (MEL) in oil into adult male hamsters at 7 p.m. (lights on 6 a.m. to 8 p.m.) for 50 days caused involution of the tests, coagulation of gland and seminal vesicles and depression in pituitary prolactin (Prl) levels. Similar injections of MEL given at 9 a.m. completely failed to cause regression of the sex organs or a depression in pituitary Prl levels. Injections of MEL in the p.m. were completely ineffective in inhibiting either the growth of the gonads and adnexa or the pituitary Prl levels if the animals had been pinealectomized. Likewise, superior cervical ganglionectomy, decentralization of the superior cervical ganglia and anterior hypothalamic deafferetation, procedures which interfere with the sympathetic nerve supply to the pineal gland, negated the ability of p.m. MEL injections to inhibit reproduction in male hamsters. The results indicate that daily MEL injections are capable of suppressing reproductive physiology in male hamsters, but only when the indole is injected late in the light period, in this case, 13 h after light on. The findings also illustrate that daily p.m. MEL injections can inhibit reproduction only in animals that have an intact and sympathetically innervated pineal gland.

Fetal ethanol exposure is known to produce CNS abnormalities. The molecular basis for these manifestations observed in animals exposed to ethanol in utero may be explained by changes in regional catecholamine content and turnover. This study was designed to determine changes in catecholamine content and turnover in the cerebral cortex, cerebellum, medial basal hypothalamus, diencephalon, and septal area of male rats exposed to ethanol pre- and postnatally. Pregnant Sprague-Dawley rats were exposed to either an ad libitum liquid diet containing 35% ethanol-derived calories, an isocalorically matched liquid diet, or a diet consisting of laboratory chow and water. Regional alterations in catecholamine content and turnover in each of the brain areas were observed on postnatal Day 18. A regional variability was demonstrated in the effect of in utero ethanol exposure on catecholamine content and turnover. The most dramatic effect was found in the dopaminergic neurons of the medial basal hypothalamus where in utero ethanol exposed offspring had a significantly reduced DA content and turnover when compared to pups from both isocalorically matched and chow-fed dams. These data indicate that the dopaminergic neurons of this particular brain region are susceptible to alteration by ethanol exposure during development and that this alteration cannot be explained by changes in nutrition alone.

This study was undertaken to ascertain ovarian function under the conditions of ethanol withdrawal and continued ethanol treatment to distinguish between a temporary delay in ovarian activity and a permanent suppression of ovarian function. Immature rats were fed the following diets for 16 weeks: a liquid diet containing 5% ethanol, a liquid diet without ethanol (pair-fed controls), a liquid diet with 5% ethanol for eight weeks followed by laboratory chow and water for eight weeks, or chow and water ad lib. Vaginal patency was significantly delayed in both groups of ethanol-treated rats compared to controls. The duration of an estrous cycle for the rats in the ad lib group was 5.0 +/- 0.3 days, while a "regular" estrous cycle was four to six days in duration. The rats which received ethanol for 16 weeks exhibited more irregular estrous cycles (both less than 4 and greater than 6 days) than the rats with other treatments and the cycles were significantly longer. After 16 weeks of treatment, the rats were mated; ethanol was not given during pregnancy. The average number of pups per litter and body weight of the offspring were similar for all groups. These data show that although ethanol alters normal cyclic activity, it does not totally suppress ovarian function since alcohol-treated rats were capable of mating and delivering viable offspring.

The effects of exogenous thyroid hormone administration on melatonin-induced gonadal atrophy were studied in young adult male hamsters. Animals were given daily afternoon injections of 25 micrograms melatonin and/or thrice-weekly injections of 7 micrograms thyroxine. A control group received injections of saline vehicle only. No significant effect of either treatment was seen on body weight. Melatonin-treated animals had significantly reduced testicular and seminal vesicle weights, compared with vehicle-treated control animals: serum T4 levels and the FT4I were reduced by melatonin treatment, but serum T3 and the FT3I were increased. No effect of melatonin was seen on in vitro T3 uptake. Thyroxine treatment alone, while leading to elevated serum T4 levels and FT4I, had no effect on T3, the FT3I, or T3 uptake. Thyroxine treatment normalized circulating T4 levels and the FT4I in melatonin-treated animals, without preventing the melatonin-induced testicular regression. The results are taken as evidence that the inhibitory effects of melatonin on gonadal and thyroid function are independently mediated.

We have examined the in utero effects of ethanol exposure on testicular steroidogenesis in newborn male pups. Pregnant Sprague-Dawley rats were fed a liquid ethanol diet (35% ethanol-derived calories), a pair-fed isocaloric liquid diet, or a standard laboratory rat chow and water diet beginning on Day 12 of gestation and continuing through parturition. Although there were no significant differences in the enzymatic activity of 5-ene-3 beta-hydroxysteroid dehydrogenase/isomerase or C17,20-lyase, the enzymatic activity of 17 alpha-hydroxylase was significantly (p less than 0.01) reduced (i.e., approximately 36%) in the ethanol-exposed pups compared to those from the pair-fed and chow treatment groups. This lesion in testicular steroidogenic enzyme activity in newborn male pups exposed to alcohol in utero was transient as 17 alpha-hydroxylase activity from the ethanol-exposed animals returned to control levels by postnatal Day 20 and remained at control levels through adulthood (postnatal Day 60). These data suggest that the suppression of the perinatal testosterone surge in male rats exposed to alcohol in utero and the associated long term demasculinizing effects of prenatal ethanol exposure might be the result of reduced testicular steroidogenic enzyme activity in the perinatal animal.

Male golden hamsters preferentially consume alcohol solution when given a free-choice between water and the alcohol solution. The pineal gland has been implicated as influencing the predilection for the ethanol solution. Melatonin, a pineal hormone, was administered either daily for 11 weeks as a subcutaneous injection (25 micrograms/animal) or weekly as a subcutaneous beeswax implant (1 mg melatonin/24 mg beeswax) for 5 weeks to hamsters allowed a free-choice between water or a 10% ethanol solution. Food, water and alcohol consumptions were measured on a daily basis. Animals treated by daily injection with melatonin consumed slightly less ethanol than animals not given melatonin. In light-deprived animals given chronic implants of melatonin, alcohol consumption was reduced when compared to alcohol consumption by light-deprived hamsters not receiving melatonin. Melatonin treatment also resulted in reducing daily total fluid intake as well as ethanol consumption in light-deprived hamsters. The results indicate that the pineal gland may influence fluid consumption in the hamster, and indirectly alters the propensity of the hamster to consume alcohol.

The purpose of this study was to determine the effect of ethanol consumption on compensatory ovarian hypertrophy (COH) which occurs following unilateral ovariectomy. Holtzman rats, 40 days old, were either unilaterally ovariectomized or sham-ovariectomized. The rats were then placed into subgroups which would receive either an ad libitum chow and water diet, a liquid diet, or a liquid diet containing 5% ethanol. The animals were maintained on their respective diets for 11 days. The rats were killed at 51 days of age, and the ovaries and uteri were removed, weighed, and prepared for histological investigation. The results showed that uteri from ethanol-fed animals failed to develop epithelial glands and exhibited a condensed stroma in comparison to uteri from animals fed ad libitum or pair-fed to ethanol-fed rats. Also, rats that were fed ad libitum had a COH of 82 +/- 16% and rats that were pair-fed a liquid diet had 114 +/- 28% COH; rats that were fed the liquid diet containing ethanol did not experience compensatory ovarian hypertrophy (-3 +/- 10%). Histologically, the ovaries of rats fed ad libitum showed large numbers of corpora lutea and only a few mature ova. The histology of ovaries from pair-fed animals was similar to those from animals fed ad libitum. In contrast, the ovaries from the animals fed the ethanol diet had nearly twice as many mature ova but only one-fourth as many corpora lutea as the number seen in ovaries from the other groups. The data show that ethanol consumption inhibits COH by suppressing ovulation and the subsequent luteal formation.

The neural membrane-bound enzymes, acetylcholinesterase, Na/K-ATPase and Ca-ATPase were examined in six brain areas in perinatal rats at 5, 15 and 25 days of age following alcohol exposure in utero. Female Wistar rats were mated with adult male Wistar rats and maintained on either a liquid diet containing ethanol (5% w/v) or on a control liquid diet for various periods during gestation and the perinatal period. These periods were: before and during gestation only (until birth of the offspring); before and during gestation and following birth; during only a period of gestation and continuing postnatally. Enzyme activity was determined by spectrophotometric methods in the following areas of the brain in each offspring: telencephalon, cerebellum, hippocampus, septal area, preoptic area, and medial basal hypothalamic area. Analysis of the data indicates that alcohol exposure in utero will heterogeneously decrease enzyme activity among the six brain areas when compared to enzyme activity in the same brain areas in animals which were not exposed to alcohol in utero. The activity of the three enzymes were most significantly reduced on day 5 of age, compared to levels in the control animals. Enzyme activity in each brain area was generally most significantly affected in animals exposed to alcohol both pre- and postnatally. The results indicate that fetal alcohol exposure reduces neuronal enzyme activity relative to the period of ethanol exposure in utero; the longer the period of time that alcohol was consumed by the mothers pre- and postnatally, the greater the effect of alcohol on the enzyme activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Pinealectomy of the Mongolian gerbil leads to seizure activity. The pineal gland is a major source of malatonin (5-methoxy-N-acetyltryptamine) which may possess a modulatory influence upon neural activity. Melatonin administered in the form of subcutaneous beeswax implants was given to gerbils four days prior to pinealectomy or sham pinealectomy. Beeswax pellets were implanted as the vehicle agent in respective groups. Melatonin-treated pinealectomized animals exhibited fewer seizures than did pinealectomized animals that did not receive melatonin. The results indicate that melatonin has an ameliorative effect upon pinealectomy-induced seizures, but the mechanism by which pinealectomy induced the seizures, and the etiology in which melatonin reduces the seizure activity is unknown.

The norepinephrine-induced inhibition of avian pineal N-acetyltransferase activity appears to be mediated by alpha 2-adrenergic receptors. In this study, alpha 2-adrenergic receptors in the chicken pineal gland were directly identified by radioligand binding. Membrane preparations of pineal glands from chickens from 1 to 6 weeks of age were examined using [3H]rauwolscine, a selective alpha 2-adrenergic receptor antagonist, to characterize the binding sites. The results indicate no ontological change in either the affinity (KD) or density of receptor binding sites (Bmax) during the time span examined. The binding was saturable and of high affinity with a mean KD of 0.27 +/- 0.01 nM and a mean Bmax of 242 +/- 12 fmol/mg protein. Further characterization of these binding sites indicated that the alpha 2-adrenergic receptor is of the alpha 2A subtype, since prazosin and ARC-239 bound with low affinities and oxymetazoline bound with high affinity.

Adult pregnant rats were given either an ad libitum liquid diet containing 5% ethanol, a pair fed liquid diet or an ad libitum diet of rat chow and water administered throughout pregnancy and during the nursing period. The female offspring received either pregnant mare's serum gonadotrophin (PMSG) or PMSG followed by human chorionic gonadotrophin (hCG) at 30 days of age. The ovaries of fetal ethanol-exposed animals responded greater to the exogenous gonadotrophins with enhanced ovarian weights, increased numbers of ova shed, greater numbers of corpora lutea and antral follicles, and higher serum progesterone levels than in animals exposed to the control diets during gestation.

Light deprivation by blinding in female hamsters was followed by a regression of the reproductive organs, an elevation of pituitary LH concentration and a depression of pituitary prolactin levels. Pinealectomy negated almost completely the effects of light deprivation on the neuroendocrine-reproductive axis. Weekly subcutaneous implants of a melatonin:beeswax pellet completely prevented the pineal gland from inhibiting reproductive physiology in blinded hamsters. The findings suggest that melatonin is not pineal antigonadotrophic factor in female golden hamsters. Melatonin implanted hamsters also had higher than normal levels of plasma prolactin.

Female hamsters were treated each afternoon for 8 weeks with subcutaneous injections of 25 micrograms of either melatonin or vehicle solution. Animals were sacrificed in either the morning or afternoon of diestrus and proestrus, along with their respective melatonin-induced acyclic pairs. Melatonin-treated hamsters had significantly greater mean body weights than did the vehicle-treated hamsters (P less than 0.05). Terminal mean serum T4 levels and free thyroxine index (FT41) were significantly reduced (P less than 0.05) in melatonin-treated hamsters compared with values obtained from animals subjected to the vehicle alone. In addition, T4 levels, FT41, T3 levels, and FT31 were significantly influenced by day and time of sacrifice independently of the melatonin treatment. T3 uptake was significantly lower on the morning of proestrus in melatonin-treated animals. These results demonstrate that chronic afternoon melatonin administration in female hamsters results in the loss of estrous cyclicity, a significant gain in body weight, and the reduction of T4 levels and T3 uptake. Changes in serum T3 levels are a function of the time of sample collection and are not influenced by melatonin treatment. In addition, these data indicate that thyroid function in general changes during the estrous cycle in these animals.

The purpose of this study was to compare the effects of different dosages of ethanol on ovarian morphology and function. Holtzman rats, 20 days old, were divided into groups as follows: The rats in Group I were autopsied at 20 days of age, and those in Group II were placed on ad libitum chow and water diet; the rats in Groups III and V were fed on a liquid diet containing 2.5% or 5% ethanol respectively; Groups IV and VI were pair-fed controls to Groups III and V, respectively. Rats in Groups II, III, IV, and VI were maintained on the diets for 50-55 days and killed at late proestrus-estrus, while the animals in Group V did not exhibit estrous cycles and were killed on day 55 of treatment. The average increase in body weights of rats in Groups II, III, and IV was significantly greater than the increase in body weights of rats given 5% ethanol or their pair-fed controls. In the rats treated with 5% ethanol, vaginal opening was significantly delayed from the controls, estrous cycles were absent, ovarian weights were similar to those of the 20-day-old rats, ovaries contained corpora lutea of only one estrus, uteri weighted less than controls, and histologically, the uteri and vaginae were similar to those of 20-day-old rats. However, in the rats treated with 2.5% ethanol, all of the parameters were similar to those of the controls. The average serum alcohol level for the rats on the 5% ethanol diet was 249 mg%; the serum alcohol levels were at the lower limit of detection for the rats on the 2.5% ethanol diet. The data show that ovarian function was suppressed in the rats that received the 5% ethanol but not in rats on the 2.5% ethanol diet.

The effect of acute ethanol administration on pineal serotonin N-acetyltransferase (NAT) activity, norepinephrine and indoleamine content was examined in male rats. When ethanol was administered in two equal doses (2 g/kg body weight) over a 4 hour period during the light phase, the nocturnal rise in NAT activity was delayed by seven hours. The nocturnal pineal norepinephrine content was not altered by ethanol except for a delay in the reduction of NE with the onset of the following light phase. Although ethanol treatment led to a significant reduction in nocturnal levels of pineal serotonin content, there was no significant effect upon pineal content of 5-hydroxyindoleacetic acid (5-HIAA). The data indicate that ethanol delays the onset of the rise of nocturnal pineal NAT activity.

Arginine vasotocin (AVT) treatment (1 microgram/injection) every two hours beginning at 06.00 h on the morning preceding expected ovulation significantly inhibited ovulation in 29-day-old immature female rats treated 2 days earlier with 30 IU of PMS. Pre-ovulatory plasma surges and pituitary decreases in LH, FSH and prolactin as measured by radioimmunoassay were not eliminated by AVT treatment. However, there appeared to be an early rise in plasma FSH in these rats and the maximum plasma LH value attained during the surge period in PMS-treated rats was elevated by AVT treatment. Arginine vasotocin significantly inhibited the increase in ovarian weight which occurs in PMS-treated rats on the day preceding ovulation and uterine weights were consistently depressed in AVT-treated rats. The results of this study indicate that AVT likely inhibits PMS-induced ovulation at the level of the ovary, although the possibility cannot be ruled out that inhibition resulted from the advancement of the plasma FSH rise. These data and other studies investigating the effects of AVT on reproduction indicate that AVT is possibly capable of acting at more than one level of the hypothalamo-hypophyseal-gonadal axis.

Intact and pinealectomized adult male hamsters kept in light:dark cycles of 14:10 (in hours) were given daily injections of either 25 microgram melatonin, 5-methoxytryptophol, N-acetylserotonin, or 6-hydroxymelatonin at 19.00 hours (13h after lights on). The injections were continued for 50 consecutive days. The daily melatonin injections significantly elevated body weights and depressed the growth of the testes and accessory sex organs and pituitary prolactin levels in intact hamsters. By comparison, in pinealectomized animals daily afternoon melatonin injections failed to alter body or testicular weights or pituitary prolactin levels. These findings indicate that for single injections of melatonin to be antigonadotrophic in the male hamster, the pineal must be intact. In intact animals, 5-methoxytryptophol and N-acetylserotonin slightly depressed the growth of the reproductive organs and pituitary prolactin levels, respectively. Again, these effects were negated by removal of the pineal gland. 6-Hydroxymelatonin was without influence on any of the parameters of reproduction that were measured.

Daily afternoon (at 7 p.m.) injections of melatonin (25 microng in oil) into adult male hamsters for 50 days led to atrophy of the testes and accessory sex organs (seminal vesicles and coagulating glands) and in a significant depression in pituitary LH and prolactin content and concentration. These actions of melatonin were prevented if the animals had been pinealectomized before the daily melatonin injections were begun. Likewise, if hamsters received a weekly subcutaneous implant of melatonin in beeswax (1 mg melatonin in 24 mg beeswax) the daily melatonin injections failed to inhibit the growth of the reproductive organs and to depress pituitary LH and prolactin levels. Beeswax by itself had no such effect.

This study is designed for better understanding the effect of chronic ethanol treatment on ovarian function in sexually mature rats by assessing the estrous cycle. Rats were fed the following diets for 17 weeks: a liquid diet containing 5% (w/v) ethanol, a liquid diet without ethanol (pair-fed) or laboratory chow and water ad lib. Estrous cycles were determined throughout the 17 weeks and the rats were necropsied at proestrus and metestrus. Ethanol-fed rats had significantly more irregular estrous cycles than did controls, and the duration of an estrous cycle in the ethanol-treated rats was statistically longer than that of controls. However, ovarian and uterine weights and ovarian and vaginal morphology of ethanol-fed rats were similar to those of controls.

We sought to determine whether superovulation could occur in immature rats on a 5% ethanol diet and treated with pregnant mare's serum gonadotropin (PMSG) alone or with human chorionic gonadotropin (hCG). Holtzman female rats were divided into five groups at 20 days of age. Six rats (Group I) were killed at that age. Ten rats (Group II) were placed on an ad libitum laboratory chow diet and killed on Day 33. Twenty-four rats (Group III) were placed on an ad libitum laboratory chow diet. Twenty-four rats (Group IV) were placed on 5% ethanol liquid diet, while 24 rats in Group V were pair-fed with the animals in Group IV. At 30 days of age, 12 rats from each Group, III, IV, and V, received 25 IU of PMSG s.c. and were killed 74-76 h later. The remaining 12 rats from each Group, III, IV and V, received 25 IU of PMSG and 54-56 h later received 10 IU of hCG and were killed 20 h later. Ovulation occurred in all the rats of Groups III and V that received PMSG alone or with hCG. In the ethanol-treated rats that received PMSG alone, 75% ovulated, while 92% ovulated that received PMSG and hCG. The number of ova shed in the ethanol-PMSG-treated rats was significantly less than in the ethanol-PMSG-hCG-treated animals and in the controls. The uterine weights and morphology of the animals in Group IV were similar to those in Groups III and V. The study indicates that ethanol does not have a direct gonadotoxic effect on the ovary but indicates that ethanol has an effect on the hypothalamus and/or the pituitary, thereby disrupting the synthesis and/or release of luteinizing hormone releasing hormone (LHRH) or luteinizing hormone (LH).

The timing of reproductive events is critically related to the exposure of a photosensitive animal to environmental light. Male hamsters were maintained in long photoperiods, short photoperiods or in darkness interrupted by brief periods (15 min) of light at 6 h intervals for 11 weeks. Gonadal atrophy did not occur in hamsters maintained in long photoperiods or in those maintained in the interrupted photoperiodic cycle, although hamsters maintained in a photoperiod of 2L:22D showed severe involution of the gonads and accessary sex glands (seminal vesicles and coagulating glands). The results indicate that the time of occurrence of environmental light during the photoperiodic cycle in which an animal is maintained is more important in determining the reproductive status of an animal than is the total amount of darkness or the dark to light ratio.

Adult male rats exposed to alcohol in utero results in reduction of the volume of the sexually dimorphic nucleus of the preoptic area (SND-POA). Reduction of the volume of this nucleus is also significantly reduced in rats exposed to ethanol postnatally compared to the volume in animals not exposed to ethanol (P less than 0.05). The results indicate that ethanol exposure during the postnatal period of brain development in rats is equally effective as in utero ethanol exposure in development of the SDN-POA volume. This report substantiates others demonstrating the deleterious effects of ethanol consumption during the 'critical' period of brain development.