Gender and estrous cycle differences in the response to the 5-HT1A agonist 8-OH-DPAT.
The effects of the 5-HT1A agonist, 8-hydroxy-2-9(di-n-propylamino)tetralin (8-OH-DPAT) on eating behavior and on rectal temperature were examined in adult male rats and in diestrous, proestrous, and estrous female rats. The 5-HT1A agonist produced evidence of hyperphagia at some dose (0.125, 0.25, 0.5 and 1.0 mg/kg) in all groups examined. However, hyperphagia was most evident in diestrous females and least evident in proestrous and estrous rats. These findings are interpreted as an estrous cycle modulation of somatodendritic 5-HT1A autoreceptors. The hypothermic response to 8-OH-DPAT was present in all females and at all doses of 8-OH-DPAT (0.1, 0.25 and 0.5 mg/kg). These findings suggest that postsynaptic 5-HT1A sites involved in 8-OH-DPAT-induced hypothermia do not vary during the estrous cycle. However, males showed less hypothermia following 8-OH-DPAT than did females. The gender difference was evidenced primarily as a slower onset of hypothermia in males treated with the lower doses of the drug.
Uphouse
L
L
Department of Biology, Texas Woman's University, Denton 76204.
Salamanca
S
S
Caldarola-Pastuszka
M
M
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D004971:Estrus; D005247:Feeding Behavior / Q000187:drug effects; D005260:Female; D006963:Hyperphagia / Q000139:chemically induced; D007035:Hypothermia / Q000139:chemically induced; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D011985:Receptors, Serotonin / Q000187:drug effects*; D012727:Sex Characteristics; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin