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The subcommissural organ (SCO) is a cerebral gland that releases into the cerebrospinal fluid a carbohydrate-rich glycoprotein which condenses to form Reissner's fiber (RF). Western blots from two-dimensional gel electrophoresis were stained with lectins (Concanavalin-A, wheat germ agglutinin) and anti-bovine RF serum to identify the secretory products of the chick embryo SCO. Immunohistochemical investigations showed that the anti-bovine RF serum reacted exclusively with the secretion of the SCO. Comparative protein patterns of SCO, pineal organ and cerebral hemisphere extracts allowed us to characterize a specific polypeptide in the SCO electrophoretic profiles. The polypeptide was a highly acid compound (isoelectric point of 4.7) with a high molecular weight (390 kDa). On Western blots only this component was immunoreactive with the RF antiserum and it exhibited an affinity for the two lectins. On the basis of these results, this polypeptide may be considered as a specific component of the secretory material synthesized by the SCO cells of the chick embryo.

The effects of 2,4,5-T on the hepatic cell in the 13 day old quail embryo have been studied. When injected at the dose level of 80 or 240 mg/kg into non-incubated eggs, this herbicide induces a proliferation of the smooth endoplasmic reticulum. The ergastoplasmic cisternae are dilated and feature a decrease in ribosomic covering. The mitochondria are swollen showing a pale matrix and a deficiency in cristae. One also observes an increase in the amount and size of lipidic inclusions and a dilatation of bile canaliculi. Moreover, biochemical analysis reveals a significant decrease in the glycogen content indicating that 2,4,5-T disturbs the glycogenic function of the liver.

The changes in the main plasma and liver metabolites of gluconeogenesis and ketogenesis have been studied in quails during 72-hr starvation. In those conditions, glycaemia barely decreased, whereas liver glycogen and plasma and liver lactate dropped, suggesting that lactate was utilized extensively for gluconeogenesis. In contrast, plasma alanine decreased only slightly. During starvation, plasma free fatty acids and cholesterol were significantly enhanced, whereas plasma triglycerides decreased. Ketogenesis seemed very active. Hydroxybutyrate concentrations were markedly higher in the plasma than in the liver, indicating that mechanisms other than simple diffusion processes should be considered for hepatic ketone body release. The present results suggest that metabolic response to prolonged starvation in the quail does not differ markedly from that observed in other birds. However, the utilization of glucose and ketone bodies by peripheral tissue and of some substrates, such as alanine or pyruvate, for gluconeogenesis must be further investigated.

Gonadal and mesonephric protein patterns from 19 day old normal chick embryos were investigated by two-dimensional polyacrylamide gel electrophoresis. Under these conditions, several sex-specific polypeptides were detected. As concerns gonadal extracts, four sex-specific polypeptides, all restricted to the cytosol, were present in the testis, whereas three sex-specific polypeptides, two localized in the cytosol, the other being membrane-bound, were identified in the ovary. Among the ovary-specific polypeptides two proved to be estrogen-dependent. They appeared in the left testis of embryos after early estradiol benzoate treatment and their expression was reduced in the ovary after early exposure to the antiestrogen, tamoxifen. Mesonephros extracts of both sexes also differed in their protein composition since three additional polypeptides (one in both the cytosolic and membrane fractions, the others in the cytosol) not found in females were found to be present in males. None appeared to be affected after either estradiol or tamoxifen treatment.

At stages 16 and 18, the germ cells counts, in the quail embryos' gonads from control and 2,4,5-T treated eggs, show no significative difference. On the contrary, at stage 20, the gonocyte numbers of the treated embryos are strongly decreased. Actually, this mechanism cannot be stage precisely.

The effects of 2,4,5-T on adult japanese quail have been studied. The herbicide was administered daily in oral dosages at level of 100 mg/kg per day for two weeks (five days a week). In these experimental conditions, this compound was moderately toxic, the rate of mortality was low. However, we noticed a significant reduction in food consumption, body weight and egg production. The physiological disturbances resulting from the toxicological treatment are reversible.