Presence of prolactin receptors in kidney and large intestine of the snake Ptyas mucosa.
125I-labeled ovine prolactin was used to test for the presence of prolactin receptors in membranes prepared from tissues of the common rat snake Ptyas mucosa. High levels of specific binding were found in kidney and large intestine membranes prepared from snakes of both sexes. The binding was time, temperature, and protein dependent. The presence of Ca2+ in the incubation medium enhanced the binding, with optimal concentrations at 10-20 mM. Specificity of binding was established by employing different hormones as the displacing species in the radioreceptor assay. The results suggested the presence of lactogenic receptors in snake kidney and large intestine membranes. Scatchard analysis of the binding data indicated the presence of a single class of binding sites in snake kidney membranes with a dissociation constant of 0.83 nM. The present study is the first report of the presence of prolactin receptors in snake kidney and large intestine membranes.
Cheng
C H
CH
Department of Biochemistry, Chinese University of Hong Kong, Shatin, N.T.
Lee
H M
HM
Ng
T B
TB
Wong
C C
CC
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005934:Glucagon / Q000494:pharmacology; D013006:Growth Hormone / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D007420:Intestine, Large / Q000187:drug effects / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D010928:Placental Lactogen / Q000494:pharmacology; D011388:Prolactin / Q000378:metabolism; D011981:Receptors, Prolactin / Q000032:analysis*; D012911:Snakes / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors
D006063:Chorionic Gonadotropin; D007328:Insulin; D011981:Receptors, Prolactin; D011388:Prolactin; D013006:Growth Hormone; D005934:Glucagon; D010928:Placental Lactogen; D002118:Calcium