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Contrary to the expectation, rats at an ambient temperature of 40°C displayed less care of the fur than rats do at an ambient temperature of 24°C. Rats in the 40°C environment curtailed their activities by lying flat; the autonomic response salival secretion appeared excessively, but the saliva was not spread on the fur by means of washing or licking. In a 4°C environment the rats displayed as much care of the fur as they do in a 24°C environment. In the 4°C environment the location of body contact for grooming changed compared to the 24°C environment. Scratching did not play a role according the lining up of the hairs during piloerection.

There is good evidence that in many species there is no effective thermoregulation in paradoxical sleep (PS), either to ambient or hypothalamic thermal stimuli. In the present work placement of pontine tegmental lesions released elaborate behaviors during PS without atonia. Regulation of brain temperature was not altered by these lesions, and shivering, piloerection, and curled posture in a cold room were lost during PS even when motor neurons were thus permanently disinhibited throughout PS. The lack of thermoregulation is considered as part of a pattern of suspension of homeostasis in highly activated states.

Three hundred and forty-seven tissue specimens were studied from 23 patients with male pattern alopecia. Characteristic features of pattern alopecia included: the presence of miniature or vellus follicles; a marked enlargement of the sebaceous glands and arrectores pilorum muscles; the presence of connective tissue streamers beneath the vellus follicles; and the thinning of the dermis. A mild perivascular infiltrate of mononuclear cells and mild capillary dilatation was sometimes seen. An increased number of mast cells was often a prominent feature. Histochemical procedures were performed for glycogen, acid mucosaccharides, inorganic substances, and enzymes including alkaline phosphatase, acid phosphatase, beta glucuronidase, cholinesterase, aminopeptidase, oxidases and dehydrogenases. Histochemical studies did not reveal any significantly abnormal enzyme changes other than the altered vascular and nerve supply to the the miniature follicles.

In unanaesthetized cats the effects were examined of propylbenzilylcholine mustard (PrBCM) on injection into the cannulated cerebral ventricles and cisterna magna. Extreme motor excitation, vocalization, shivering leading to fever, tachypnoea, panting, piloerection and salivation were produced on ventricular, vigorous scratching bouts on cisternal, injections. The sites of these actions are discussed. None of the effects was produced by atropine similarly injected. All effects were suppressed by anaesthetizing doses of pentobarbitone sodium injected intraperitoneally.

Cats with lesions of hippocampus or of prefrontal cortex showed changes in several species-typical behavior patterns. Both hippocampal and frontal operates were submissive to intact cats during social pairings, but the nature of the submissive behavior differed qualitatively in the two groups. Cats with hippocampal ablation showed little affective response to social threat or to a threatening cat model, whereas cats with frontal lesions responded appropriately to threat (albeit submissively). Both lesions affected some components of the animals' response pattern to the odor of cat urine. Hippocampal removal enhanced the occurrence of the “gape” response and retarded intersession habituation of the “sniff” and “nose lick” components, Frontal cortex ablation eliminated the “gape” response but did not affect habituation. The results are interpreted as supporting the hypothesis that both hippocampus and prefrontal cortex are involved in the assessment of the biological significance of environmental stimuli.

Clonidine, lidamidine, and loperamide each inhibited castor oil-induced diarrhea in the rat. Clonidine and lidamidine, but not loperamide, also induced diuresis but at doeses above those producing antidiarrheal activity. Clonidine and lidamidine, but not loperamide, produced autonomic and central effects including piloerection, hypotonia, exopthalmus and ataxia at doeses similar to those producing antidiarrheal activity. These data suggest that only loperamide possesses selective antidiarrheal activity.

Rats with lesions in the region ventral to the anterior septum were tested in a novel situation for attack on a young adult rat and attack on a mouse. To determine whether they would also show enhanced social attack behavior, the lesioned animals that attacked the rat or killed a mouse in the paired encounter were tested 2 days later in a group colony composed of male and female adult rats and in some cases rat pups. Lesioned rats that attacked a young rat or killed a mouse in the paired encounter never developed piloerection or attacked resident males of the colony group. The lesioned animals did attack rat pups in the colony situation and also attacked females in the vicinity of the rat pups. Spontaneous mouse-killing rats also failed to attack males in the colony groups, but did attack rat pups and females. Alpha-male rats did develop piloerection and attacked resident males when introduced as intruders into a colony group. The alpha males did not attack rat pups or females in the colony group. Two of nine sham-operated rats developed piloerection and attacked males in the colony group situation, although none attacked the rat pup or the mouse in the paired encounter. It is inferred that rats with lesions ventral to the anterior septum do not show enhanced intraspecific social attack behavior similar to that of alpha-male rats.

• Congenital pigmented arrector pili hamartomas are unique malformations of epidermis and pilar apparatus usually appearing as localized, lightly pigmented, hairy plaques. Characteristic microscopic features include smooth-muscle proliferation similar to irregularly disposed arrectores pilorum, and slight elongation of epidermal rete with hypermelanosis of the basal unit. An otherwise normally developed child who had this hamartoma at birth is described in an attempt to clarify the relationship between pilar smooth-muscle hamartomas and Becker's melanosis. We propose that these two entities belong at different poles of the same developmental spectrum of hamartomatous change. ( Arch Dermatol 1985;121:1034-1037)

Regions containing heat gain tonic inhibitory areas in mesencephalon and upper pons were studied using topical microinjection of a local anesthetic. This inhibition was compared in the mesencephalic decerebrated and intact animals. In mesencephalic animals that failed to shiver, bilateral injections of procaine into the ventromedial pontine tegmental areas released some heat gain responses and in intact anesthetized cats injections in the same regions increased intensity of shivering. These effects on inhibitory areas are reversible and can be repeated in the same preparation several times. Permanent effects were obtained by electrolytic lesions or by the local microinjections of 1% osmic acid. In summary, it is shown, by means of microinjection of local anesthetic, that a tonic inhibitory area located in the ventromedial pontine reticular formation completely inhibits shivering in the mesencephalic decerebrate preparation and partially inhibits shivering in the intact anesthetized preparation.

The intermale social aggressive behavior of male rats cohabiting with a female rat was quantitatively scored weekly in response to the introduction of an unfamiliar intruding male. Resident male rats whose aggressiveness toward an intruder reached a criterion level were subjected to either sham lesions or bilateral lesions in the region of the medial preoptic area. The lesioned rats continued to exhibit levels of piloerection and lateral attack that were not significantly lower than those of sham-lesioned animals. However, the lesioned animals did emit significantly fewer bites and spent significantly less time in the "on-top" position than did sham-lesioned animals. The lesioned animals also displayed significantly less sexual behavior than the sham-lesioned animals but were not different in terms of defensiveness toward the experimenter. It is suggested that bilateral lesions in the region of the medial preoptic area cause a decrease in the intensity of intermale social aggression but do not prevent external stimuli from eliciting the aggression.

A total of 12 heterosexual pairs of marmosets were observed at different stages after pairing. Social behaviour (including contact, proximity and grooming) and sexual behaviour (mating and soliciting behaviour) were more frequently observed in recently formed pairs than in pairs that had been housed together for longer periods. Some behaviour patterns were performed more frequently by one sex and in general these sex-related differences were evident irrespective of the length of pairing. The performance of simultaneous piloerection and play appeared to be related to the reproductive state of the female. Males became more responsible for initiating contact during the latter part of the females’ pregnancy. Mating continued at low levels during pregnancy.

Summary: Pilomotor epilepsy is a rare phenomenon. A 35-year-old man suffered a traumatic contusion of the right temporal lobe and subsequently developed spells characterized by diffuse piloerection and sweating. We believe this to be the first reported association between pilomotor epilepsy and posttraumatic head injury. Al-though pilomotor seizures may result from diverse etiologies, they appear to have a common involvement of tem-porolimbic structures. RESUME Ľepilepsie pilomotrice est rare. Un homme de 35 ans, qui avait subi une contusion traumatique du lobe temporal droit, a presente par la suite des acces caracterises par une pilo-erection diffuse et une sudation. Les auteurs pensent que ce cas rep-rtsente la premiere observation d'une association epilepsie pilo-motrice-traumatisme cranien. Les crises pilomotrice rtpondent a des Etiologies varices, mais semblent avoir en commun une participation des structures temporo-limbiques. RESUMEN La epilepsia “pilomotora” es un fenomeno raro. Un enfermo de 35 anos de edad que habi'a sufrido una contuseon traumatica en el lobulo temporal derecho, desarrolUS ataques caracterizados por una piloereccidn y sudoraci6n difusa. Creemos que este es el primer caso publicado en el que se asocia la epilepsia polomotora y un traumatismo craneoencefalico. Aunque los ataques pilomo-tores pueden ser el resultado de diversas etiologias, parece ser que, en todos ellos, es comun una afectaci6n de las estructuras li'mbicas del lobulo temporal. ZUSAMMENFASSUNG Die pilomotorische epilepsie ist selten. Ein 35-jahriger Patient litt an einer traumatischen Kontusion des rechten Temporallap-pens und entwickelte Anfalle mit diffuser Piloerektion und Schwitzen. Wir halten dies fur eine erstmalig beschriebene Verknupfung zwischen posttraumatischer Hirnverletzung und pilomotorischer Epilepsie. Da pilomotorische Anfalle durch ver-schiedene Atiologien verursacht werden, scheint ihnen im allge-meinen eine Beeintrachtigung temporo-limbischer Strukturen zugrunde zu liegen.

Aspects of social structure in group-living species can be inferred by observing the responses of individuals to unfamiliar animals. This study examined the responses of mated pairs of cotton-top tamarins (Saguinus oedipus oedipus) to presentation of either unfamiliar conspecifics or members of a related tamarin species, the saddle-back tamarin (Saguinus fuscicollis fuscicollis). Male and female responses to intruders differed: resident males threatened, displayed piloerection, approached, and attacked intruders, especially males, while resident females showed increases in suprapubic scentmarking in the presence of intruders. Both males and females discriminated between the species of intruders, exhibiting more threats, scent-marking, piloerection, and approaches in the presence of conspecific intruders. There are pronounced sex differences in the signals and behaviour patterns that are elicited in an aggressive or territorial encounter with unfamiliar conspecifics in this monogamous primate.

Stereotyped hyperactivity in rats following combined administration of tranylcypromine, a monoamine oxidase (MAO) inhibitor, and tryptophan has been attributed to an extraneuronal excess of 5-hydroxytryptamine (5-HT). Similar conditions might arise from concomitant inhibition of MAO and 5-HT uptake. We now report the effects of two specific inhibitors of 5-HT uptake-5-hydroxymethtryptoline and Lilly 110140. When given in combination with tranylcypromine, both uptake inhibitors produced a hyperactivity syndrome which was indistinguishable from that following tranylcypromine and tryptophan; and, p -CPA-pretreatment blocked the syndrome.

Two longitudinal studies were conducted to quantify the social behaviors exhibited by both male and female Long-Evans rats from the immediate postweaning period until young adulthood. In Experiment 1, male sibling pairs engaged in a high level of play fighting during the early juvenile period but such activity declined to a level significantly lower than that of female and mixed-sex pairs after 54 days of age. In Experiment 2, social exchanges during maturation were examined during the presence and absence of the piloerection response in an effort to distinguish play fighting from agonistic interactions. In male pairs, piloerection was rarely seen before 55–75 days of age but thereafter occurred with increasing frequency especially among dominant males. Furthermore, subordinate males retreated from their dominant partners and remained in an escape chamber for a significant amount of time only during encounters involving the exhibition of piloerection. This finding suggests that piloerection can be useful in identifying play and aggressive interactions. In female and heterosexual pairs, piloerection was observed infrequently during social encounters occurring throughout maturation. In addition, when given the opportunity to escape, females were less likely to retreat from play activity if their partner was another female than a male.

The organization of pre- and postganglionic neurons supplying blood vessels of the skin (vasoconstrictor neurons) and of the skeletal muscle (vasoconstrictor neurons), sweat glands (sudomotor neurons) and erector pilimuscles (pilomotor neurons) of the cat's hind limb and tail is discussed. Each sympathetic subsystem has its own, though as yet unknown, central organization which is reflected in the reaction patterns typically seen. The conduction velocities of the pre- and postganglionic axons of each subsystem have their unique distributions. Postganglionic vasoconstrictor neurons supplying skeletal muscle and skin are influenced via cholinergic muscarinic and non-cholinergic synaptic mechanisms from thin, probably unmyelinated, preganglionic axons; postganglionic sudomotor and pilomotor neurons most likely do not receive this synaptic input. A high proportion of preganglionic neurons projecting with their axons onto postganglionic neurons which supply skin and skeletal muscle are silent and do not exhibit reflex activity. Some of these neurons synapse with postganglionic pilomotor, vasodilatator and sudomotor neurons; part of them may also synapse with vasoconstrictor neurons. However, the high proportion of preganglionic neurons without reflex and resting activity which cannot be classified on the basis of functional properties presents a considerable problem in the analysis of the central organization of the sympathetic nervous system. It is concluded that the 4 types of pre- and postganglionic neurons mentioned constitute 4 largely separate channels which transmit information from the spinal cord to the respective target organs.

The occurrence of preterm labor is not uncommon in the pregnant quadriplegic. Early diagnosis is hampered by the inability of most quadriplegics to sense uterine contractions in the usual way. A patient we recently treated for preterm labor learned to recognize contractions by the associated symptoms of autonomic hyper-reflexia: flushing, headache, and piloerection. Tocolytic therapy was successful and a favorable neonatal outcome occurred. Increased awareness by the physician and the pregnant quadriplegic patient is encouraged so that symptoms of autonomic hyper-reflexia may be recognized as potentially indicative of uterine contractions.

The fluorescence histochemical method of Falck-Hillarp ('62) demonstrates dense plexuses of catecholamine-containing nerves in the piloarrector muscles of adult stump-tailed macaques. When these muscle fibers are viewed under the electron microscope, most of the axon terminal profiles between them contain numerous dense-cored vesicles (adrenergic); the rest of the terminals contain mainly agranular vesicles (cholinergic). Intradermal injections of 6-hydroxydopamine (6-OHDA, 1 and 5 mg) or 5-hydroxydopamine (5-OHDA, 10 mg) into the scalp caused the fluorescence from the nerve fibers in the muscles to completely disappear. The 6-OHDA injections induced severe degenerative changes in the adrenergic terminals whereas the 5-OHDA injections caused only the granules in the vesicles to increase in numbers. Thus, the piloarrector muscles of these macaques are innervated with both adrenergic and cholinergic terminals, but the former are more numerous than the latter.

Specific agonistic responses of albino rats were compared for dominant colony rats and intruders, and for rats in a “reflexive fighting” task. The “reflexive fighters” showed high levels of defensive responses such as boxing and freezing, and very low levels of aggressive behaviors such as piloerection, biting, and the lateral display. This pattern clearly suggests that the behaviors measured in the reflexive fighting task reflect conspecific defensive reactions, rather than “shockelicited aggression.” Moreover, striking responses seen in the reflexive fighting task also occur at a high rate when footshock is given to a solitary rat held in a boxing posture. Thus it appears that “reflexive fighting” primarily involves defensive rather than aggressive responses.

Intraperitoneal injections of mevinphos with doses ranging from 0.20 to 4.00 mg/kg were given to gerbils. Various somatic signs of poisoning, such as ataxia, piloerection, tremor, salivation, and convulsions, were noted. Somatic signs were observed in all cases; in all but two cases, effects were evident within 90 sec after injection. Animals were observed for at least 30 min following injection and, in lethal cases, time to death was recorded. LD50 values of approximately 0.45 mg/kg for males and 0.54 mg/kg for females were obtained. Females were more resistant to the chemical.

The purpose of this study was to determine which types of mechanoreceptor afferents contribute to sympathetically evoked activity in wide-dynamic-range (WDR) neurons--the spinal neurons thought to mediate sympathetically maintained pain. The experimental approach was to record and compare activity evoked in single WDR neurons, hair afferents, and slowly adapting type I (SAI) afferents in anesthetized cats. During electrical stimulation of the sympathetic trunk, WDR neurons responded with either an early transient burst of activity, sustained activity, or both. The early transient response was observed only in neurons with piloerection in the receptive field; this response had a similar time course to sympathetically evoked activity in hair afferents with piloerection in the receptive field. The sustained response that occurred in some WDR neurons was independent of piloerection and was similar in time course to the response evoked in SAI afferents by sympathetic stimulation. We conclude that hair and SAI afferents contribute to different components of sympathetically evoked activity in WDR neurons and that both types of afferents are likely to be involved in sympathetically maintained pain in humans.

Pyrogenic responses to intravenous injections of typhoid vaccine were studied in intact and acute high- and low-level decerebrate monkeys (Macaca cyclopis). Responses in intact animals were characterized by drowsiness, increasing rectal and decreasing cutaneous temperatures of soles of the feet. Piloerection and shivering occurred after a latency of 30 min. Febrile responses of 2.3 ± 0.5°C peaked at 2 h. Soon after piloerection and shivering decreased and temperature of the soles stabilized. Body temperature returned to normal by 6 h. Side reactions of retching, vomiting, defecation, and urination were frequently noted. High-decerebrate preparations (brain stem truncated in the mesencephalon) showed no pyrogenic responses but urinated and defecated. Low-level preparations (truncated just rostral to the trapezoid body) showed all pyrogenic responses noted in intact animals, except drowsiness. Shivering and all side reactions were more marked than in intact animals. Latencies for onset of febrile response, maximum response, and defervescence were quite similar. Low-decerebrate animals showed a febrile peak of 1.6 to 2.3°C irrespective of “set point” for thermal regulation (animals regulating at 37.9 ± 0.3°C peaked at 1.9 ± 0.3°C; at 35.8 ± 0.2°C peaked at 2.2 ± 0.1°C; at 39.5°C peaked at 2.1°C). Febrile responses to bacterial pyrogens are not dependent on integrity of the hypothalamus and high-decerebrate preparations fail to show febrile responses because thermoregulatory heat gain mechanisms are tonically inhibited by released mesencephalic and rostral pontine tegmental systems. Lowering the decerebration to the level of the trapezoid body abolished released inhibition and restored thermoregulatory responses to cooling and febrile reactions to bacterial pyrogens.

Specific behaviors comprising the serotonin syndrome (low body posture, forepaw treading, headweaving) and the autonomic signs of piloerection and salivation were determined and analyzed with locomotor activity in response to MDMA at three doses (2.5, 5.0, and 7.5 mg/kg). All behaviors were dose-responsive. Serotonin syndrome behaviors increased in both intensity and duration of response with increasing doses. In contrast, locomotion varied only in intensity. Subchronic injections, in the same group of animals, permitted an analysis of acute vs. subchronic effects on these same behaviors. Both the serotonin syndrome and locomotor behaviors were augmented on subsequent testing, indicating that, (+/-)MDMA, like amphetamine, is capable of producing behavioral sensitization.

1. The thermoregulatory responses of pigeons were tested by selective and combined cooling and heating of thermodes implanted chronically into the brain stem and vertebral canal. 2. Under thermoneutral conditions lowering the brain temperature to 36°C did not elicit shivering. Similar stimulations of the spinal cord evoked shivering in each case. Simultaneous temperature changes in same direction (cooling the brain and spinal cord) or in opposite direction (heating the brain and cooling the spinal cord) could not influence the intensity of shivering due to cooling the spinal cord alone. Thermal stimulation of the brain stem did not affect shivering due to environmental cold, whereas this response was intensified by cooling and diminished by heating the spinal cord. 3. Selective heating of the brain to 44°C rarely induced panting, whereas heating the spinal cord to 42–43°C resulted generally in polypnea under thermoneutral conditions. Opposite changes at both sites (heating the spinal cord and cooling the brain) inhibited panting due to heating the spinal cord in 3 of 12 cases. Under conditions of environmental heat, persisting thermal panting was often inhibited by cooling the spinal cord, but hardly affected by cooling the brain stem. 4. Cooling the brain as well as the spinal cord raised the feathers (piloerection) and lowered the skin temperature of the naked feet (vasoconstriction). Both reactions were affected to about the same extent by stimuli in each of the two parts of CNS. 5. The results suggest that the temperature signals generated in the brain stem of the pigeon especially effect piloerection and vasomotor reactions. These responses enable the animals to maintain a constant deep body temperature under mild thermal load. Changes of the spinal cord temperature chiefly drive shivering and panting which avoid hypo- and hyperthermia of birds under stronger thermal stress.

The central effects of LiCl were examined with the following results. 1) LiCl in doses of 600_??_800mg/kg i. p. or 40_??_80μg i. c. decreased spontaneous motor activity in mice as measured by either the wheel cage or the photocell counters methods. 2) LiCl in doses of either 400mg/kg i. p. or 20μg i. c., which did not influence the spontaneous motor activity in mice, markedly blocked the conditioned avoidance response but not the unconditioned. 3) LiCl in doses of 100mg/kg or 20μg i. c. blocked the biting, attacking and vocalization in the electroshock induced aggressive behavior including attacking, biting, vocalization, jumping and piloerection. 4) LiCl in doses of 600mg/kg i. p. or 80μg i. c. did. not influence catecholamines or 5-HT in mouse brain.

A method has been described for the study of the central effects produced by the intracerebral injection of drugs in the unanaesthetized mouse. The effects observed were in good agreement with those obtained after similar injections in cats, dogs and human beings. After intracerebral injection, drugs of diverse structure produced certain generalized effects: changes in positioning of the tail, stupor, hyperexcitability and tachypnoea. Both acetylcholine and methacholine produced an akinetic seizure and depression, but the latter compound also caused lacrimation and salivation. Atropine produced piloerection, increased sensitivity to sound and touch, clonic convulsions and scratching, whereas hexamethonium caused Parkinsonian-like muscle tremors and peripheral vasodilatation. After adrenaline, hyperexcitability, exophthalmos, stupor and death from pulmonary oedema were observed, but (+)-methylamphetamine produced only piloerection and exaggerated activity in response to sound and touch. Ergotamine caused a decreased sensitivity to sound and touch, micturition, and stupor, while ergometrine caused clonic convulsions, piloerection, defaecation and stupor.

Intradermal tetraethylammonium ion (TEA) produces local sweating and piloerection which may be cyclic, a peculiar local tingling and apparent vasoconstriction. These effects are inhibited by local procaine and by peripheral or sympathetic nerve block. Other ganglionic blocking agents and chemical analogs of TEA do not share these actions. It is concluded that TEA potentiates, at the neuroeffector junction mechanism, background tone of the nerves innervating the cutaneous effectors. Submitted on September 3, 1957

In normal warm-adapted mice a lowering of the ambient temperature to 0 °C was followed by piloerection, shivering, and an increase of oxygen consumption, which prevented a serious hypothermia. The survival rate after 4 h cold exposure was 82%. Mice pretreated with a β-receptor blocking agent, propranolol, MJ 1999, or INPEA, showed piloerection and shivering when exposed to 0 °C, but their ability to increase heat production was impaired. Depending upon the dose of the β-receptor blocking agent used, the increase in the metabolic rate was diminished, and rectal temperature and survival rate dropped sharply. After 25 μg/g MJ 1999, only 13% of the animals survived. After 20 μg/g propranolol or 100 μg/g INPEA all animals died. The results give evidence for the importance of the sympatho–adrenal system in general for the maintenance of body temperature and the survival after acute cold exposure, and for the special importance of the adrenergic β-receptors, which are necessary for the animals to increase their heat production.

“Some effects of the hallucinogenic drug, 2,5-dimethoxy-4-methyl amphetamine on the metabolism of biogenic amines in the rat brain”. B. E. Leonard, Pharmacology Section, Imperial Chemical Industries Limited, Pharmaceuticals Division, Alderly Park, Nr. Macclesfield, Cheshire.

The postnatal development of agonistic behavior patterns in the wolf, coyote and grey fox are described, and in the red and Arctic fox which were first observed at a later age. Piloerection and back arching were present in all species, the latter behavior being especially well developed in the grey fox. The orientation of attack was almost exclusively directed at the cheek in the grey fox, but in other canids the shoulder hackle area, throat and muzzle area were also attacked; prolonged bouts of jaw-muzzle wrestling occurred in the wolf, scruff-wrestling in wolf and coyote and dog, and cheek-wrestling in the grey fox during agonistic play (play-fighting). Orientation of attack was correlated with distinctive body markings in various species. The contribution of social experience in the ontogeny of scruff-oriented attack was demonstrated in hand-raised isolated dogs and visually deprived group-raised dogs. The significance of head-turning, looking away and avoidance of eye contact in the wolf and dog is discussed.

The sweat glands of the horse are very sensitive to L-adrenaline, 0·5 to 1·0 μ g/kg, i-v. being enough to cause general sweating. Given intradermally, the threshold dose is usually about 0·1 μ g; this causes local sweating, lasting for an hour or more, and spreading as a clear-cut track along superficial lymphatic vessels for long distances. This striking result has not previously been recognized. The action of adrenaline is not inhibited by any of seven adrenaline antagonists which were tried. No piloerection is caused within a few hours by adrenaline. L- nor -Adrenaline, by either route causes no sweating, or only a little locally an hour or two after i-d. injection; but tracks of hair erection identical with the adrenaline sweating tracks appear, and on i-v. injection in doses of 5 mg or over, general piloerection occurs. The piloerection is inhibited by dibenamine. Parasympathomimetic substances (acetylcholine, Carbachol) cause sweating when given in suitable doses, either i-d. or i-v.; their action is inhibited by atropine, and augmented by anticholinesterases. The sweating on i-v. injection is probably due to adrenaline release from the adrenals, that on i-d. injection to skin vaso-dilatation. Factors which increase the skin circulation favour, or cause, sweating, and vice versa. Hence sympathetic denervation leads to prolonged and profuse sweating, and subsequently to an increased tendency to sweat, lasting for more than 3 months. There is little evidence to favour the view that the sweat glands in the horse normally respond to, or are provided with the necessary innervation for, the action of nerves, sym­pathetic or otherwise, but strong evidence that they normally respond to an increase in the amount of adrenaline in the blood, or to increased blood supply. The latter is under nervous control. After i-d. injections of adrenaline the skin is anhidrotic for some days. This may throw light on the condition of tropical anhidrosis.

1. In the unanaesthetized monkey (Macaca cyclopis), heating the spinal cord or the medulla oblongata from 38 to 42-43 degrees C produced subcutaneous vasodilatation, respiratory acceleration (frequently interrupted with a period of apnoea in the medullary experiment), bradycardia and hypotension. The animal became drowsy and had a slight decrease of body temperature. Heating the medulla oblongata often induced retching and/or emesis.2. Cooling the spinal cord or medulla oblongata from 38 to 32-33 degrees C produced subcutaneous vasoconstriction, slower respiration, tachycardia and hypertension. The animal became restless and had a slight increase of body temperature. Cooling the spinal cord induced shivering of the four limbs, while cooling the medulla oblongata induced only shivering of the jaws.3. The effects of heating or cooling of the spinal cord or the medulla oblongata were antagonized by simultaneous application of temperature displacement of the opposite nature in the same areas or vice versa.4. The data suggest that some thermosensitive elements possibly responsible for thermoregulation reside in the spinal cord and the medulla oblongata.

Publisher Summary Fever is a major manifestation of the acute phase of the immune response to infection caused by a variety of microorganisms and viruses. Prostaglandins (PGs) having a role in fever was first intimated when scientists reported that prostaglandin E1, when injected into the cerebral ventricles of the conscious cat, produced a rise in deep body temperature. The rise in temperature was accompanied by shivering, piloerection, vasoconstriction, and with the animals taking up a curled up position. PGs increase body temperature by increasing heat production and decreasing heat loss. This chapter shows that the synthesis of the prostaglandins could be inhibited by aspirin-like drugs and proposes that all the three actions of these drugs—namely, antipyretic, analgesic and anti-inflammatory are mediated by the inhibition of prostaglandin synthesis. The experiments on the effects of PGE1 and PGE2 show quite clearly that prostaglandins raise body temperature by a coordinated increase in heat production and a decrease in heat loss. Body temperature rises until a new equilibrium has been reached.

A case is reported of a phaeochromocytoma revealed during a general anaesthesia by a sudden hypertensive crisis associated with acute pulmonary oedema and signs of extreme sympathetic stimulation (bilateral mydriasis, piloerection, peripheral vasoconstriction). Aortic angiography revealed the tumour lying in an ectopic retroperitoneal situation and spasm in the superior mesenteric arterial territory. The patient died at the thirtieth hour from septic shock due to necrotizing colitis.

The administration of p-chlorophenylalanine to mice prevents the rise in brain 5-hydroxytryptamine concentration associated with ethanol withdrawal but does not affect the increase in brain catecholamines which occurs at the same time. The locomotor excitement, piloerection, tremor and handling convulsions which occur during ethanol withdrawal were not affected. These results suggest that the increase in brain 5-hydroxytryptamine which occurs in ethanol withdrawal is a consequence of increased 5-hydroxytryptamine synthesis and that it is probably not involved in the above behavioural changes of ethanol withdrawal.

The centrally induced effects of 5-HT and LSD and three of its derivatives have been studied following intracerebral injection in conscious mice. The symptoms observed after giving 5-HT were scratching and stupor. LSD and its derivatives caused hyperexcitability, piloerection, muscle incoordination, and sensitivity to touch. LSD also produced a sensitivity to sound, a muscle twitch in the lumbar area and a peculiar alternating stamping of the feet. LSD, 1-acetyl-LSD and 1-methyl-LSD were able to block the central effects of 5-HT whereas d -lysergic acid dimethylamide did not antagonize 5-HT.

Intracerebral injection of 0.5-1.0 µ g. of neostigmine or eserine in the conscious mouse causes the following effects: tachypnea followed by bradypnea, piloerection, lacrimation, salivation, exophthalmos, micturition, defecation, muscle spasms and tremors, loss of control of the fore limbs and generalized depression. The central sites of action producing these peripheral effects are discussed.

The effects of patulin when given into the third cerebral ventricle of rats, on behaviour and electrocortical spectrum power have been investigated. Patulin (10 μg i.v.t.) produced behavioural sedation, hypoalgesia, tail rigidity, piloerection and postural changes. This symptomatology lasted approx. 3 h and was accompanied by slower frequency and larger amplitude potentials in the electrocorticogram (ECoG) and by an increase in total voltage power. A larger dose (50 μg) produced a more dramatic picture characterized by catatonic posture with kyphosis, loss of the righting reflex, tail rigidity and on a few occasions short-duration episodes of tonic-clonic convulsions. Such a symptomatology was accompanied by a flattening of ECoG activity with a significant fall in total voltage power, as well as in preselected bands (0–3, 3–6, 6–9, 9–12, and 12–16 Hz). A lower dose (1 μg) of patulin, on the other hand, produced behavioural sedation without significant changes in ECoG spectrum power.