EFFECTS OF INTRACEREBROVENTRICULAR PROSTAGLANDINS E2 AND F2α ON THE URINE OUTFLOW, AND a POSSIBLE ROLE OF PGE2 AS a MODULATOR

The Effects of Prostaglandin Synthetase Inhibitor Indomethacin on the Hypothalamic and Neurohypophysial Oxytocin Content in Euhydrated and Dehydrated Male White Rats1)

“…It seems therefore that the increased neurohypophysial oxytocin content, brought about by repeated administration of indomethacin to euhydrated animals (this study), might be related to decrease of oxytocin release due in turn to impaired prostaglandin formation. In this respect, the present observations are consistent with previous reports indicating stimulation of oxytocin release in consequence of treatment with prostaglandins (Ellendorff et al, 1978;Fujimoto et al, 1978;Gillespie et al, 1972). Furthermore, indomethacin was recently reported to suppress the pulsatile release of oxytocin in the goat (Cooke and Homeida, 1984).…”

“…A number of reports established the formation of prostaglandins in the central nervous system of the rat; in addition to PGE2 and PGF2alpha (Abdel-Halim et al, 1978), also PGD2 was recently shown to be present in the brain and neurohypophysis (Narumiya et al, 1982). The physiological role of prostaglandins in the central nervous system was widely discussed: it was suggested that prostaglandins act as neurotransmitters, but it is possible as well that they act as neuromodulators (Fujimoto and usada, 1978). There is no general agreement in that question (Gilbert et aI., 1978).…”

“…There is as well some evidence indicating influence of prostaglaridins on the hypothalamic neurosecretory neurones (Biswas and Gosh, 1976). Prostaglandins are known to affect the release of vasopressin (Ishikawa et al, 1981) and oxytocin (Fujimoto et al, 1978;Ellendorff et al, 1978).…”

“…Some years ago Priluski and Deis (1976) reported that administration of PGFSalpha in lactating rats is followed by changes of milk ejection, possibly mediated through modified release of oxytocin. When injected into the cerebral ventricle, PGFSalpha and PGE2 were noted to exert oxytocic effects in rats (Fujimoto et al, 1978); in these experiments changes of the uterine pressure were chosen as a functional index. Injection of PGF2aIpha in the pig is followed by an increase of the oxytocin concentration in blood plasma (Ellendorff et al, 1978); similar effects of PGF2alpha were observed in the human (Gillespie et al, 1972).…”

Antidiuretic and thermogenic effects of intracerebroventricular prostaglandin H2 in ethanol-anaesthetized rats

“…For example in the Dipteron Musca domestiea, a female specific attracting substance, cis-9-tricosene, was isolated in 1971 by Carlson et al 4. One or both sexes produce pheromones which induce specific behavioral responses of the mate.…”