Suppression of the prolactin surges in the pseudopregnant rat by urethane anesthesia.
In pseudopregnancy of the rat prolactin (PRL) is released in the form of twice daily surges (nocturnal and diurnal surges). An attempt was made to examine the effects of urethane anesthesia on PRL surges during pseudopregnancy of the rat. In a preliminary study, using the continuous blood sampling method, the nocturnal PRL surge was completely blocked when urethane (1.0g/kg BW) was administered at 0:00 hr. Urethane (1.0g/kg BW) was injected at 0:00 or 12:00 hr, and serum and pituitary PRL concentrations were measured at 6:00 or 18:00 hr, respectively, to study the effects of urethane on nocturnal or diurnal PRL surges. There were no serum PRL surges during either the nocturnal or diurnal periods following urethane injection. The experiment examining pituitary PRL concentration at 6:00 or 18:00 hr confirmed that urethane (1.0g/kg) anesthesia suppressed the release of PRL surge from the pituitary.
Furudate
S
S
Department of Laboratory Animal Science, Kitasato University School of Medicine, Kanagawa, Japan.
D000758:Anesthesia; D000818:Animals; D002940:Circadian Rhythm; D005260:Female; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism*; D011555:Pseudopregnancy / Q000503:physiopathology / Q000662:veterinary*; D051381:Rats; D014520:Urethane / Q000494:pharmacology
D014520:Urethane; D011388:Prolactin