TY - JOUR
T1 - Increased serum prolactin levels mediate the suppressive effects of ectopic pituitary grafts on copulatory behavior in male rats
AU - Doherty, Paul C.
AU - Bartke, Andrzej
AU - Smith, M. Susan
AU - Davis, Steven L.
N1 - Funding Information:
Materials and kits for hormone injection and radioimmunoassayo f rat PRL and ovine PRL were generouslyp rovided by the Hormone DistributionP rogram,N IAMDD, and Dr. A. F. Parlow. We wish to thank Ms. Lynn Rudloff and Ms. GrettaS mall for their assistance in preparing this manuscript. This work was supported by NIH Grants P30 HD10202 (Bioassay Core) and HD12671.
PY - 1985/6
Y1 - 1985/6
N2 - To determine if deficits in sexual activity, observed in pituitary-grafted male rats are due to elevated serum prolactin (PRL) levels found in these animals, the effects of whole pituitary grafts, pars distalis grafts, and ovine (o) PRL treatment on male copulatory behavior were compared. Adult sexually experienced CDF male rats were given four whole pituitary grafts, four pars distalis grafts, or were sham operated. Both groups of grafted animals exhibited suppressed copulatory behavior patterns when tested 18 days after pituitary transplantation. Animals given whole pituitary grafts had significantly longer latencies to mount (P < 0.05) and to intromit (P < 0.01) than did the sham-operated controls, while the animals given anterior pituitary grafts differed from the sham-operated controls in latencies to mount (P < 0.05) and to intromit (P < 0.01), as well as in the number of intromissions (P < 0.05). Prolactin-injected animals had significantly reduced intromission rates (P < 0.01) and significantly increased latencies to mount (P < 0.05) and to intromit (P < 0.01) when compared to vehicle-injected controls. Furthermore, the time course of behavioral suppression was similar in oPRL-treated animals to that observed in pars distalis-grafted males, with both groups showing the onset of deficits in sexual activity within 8 to 9 days from the induction of the hyperprolactinemic state. The similarity in pattern and time to onset of behavioral suppression in pituitary-grafted and oPRL-treated animals suggests that behavioral deficits observed in animals with pituitary grafts result from chronic elevation of serum PRL levels.
AB - To determine if deficits in sexual activity, observed in pituitary-grafted male rats are due to elevated serum prolactin (PRL) levels found in these animals, the effects of whole pituitary grafts, pars distalis grafts, and ovine (o) PRL treatment on male copulatory behavior were compared. Adult sexually experienced CDF male rats were given four whole pituitary grafts, four pars distalis grafts, or were sham operated. Both groups of grafted animals exhibited suppressed copulatory behavior patterns when tested 18 days after pituitary transplantation. Animals given whole pituitary grafts had significantly longer latencies to mount (P < 0.05) and to intromit (P < 0.01) than did the sham-operated controls, while the animals given anterior pituitary grafts differed from the sham-operated controls in latencies to mount (P < 0.05) and to intromit (P < 0.01), as well as in the number of intromissions (P < 0.05). Prolactin-injected animals had significantly reduced intromission rates (P < 0.01) and significantly increased latencies to mount (P < 0.05) and to intromit (P < 0.01) when compared to vehicle-injected controls. Furthermore, the time course of behavioral suppression was similar in oPRL-treated animals to that observed in pars distalis-grafted males, with both groups showing the onset of deficits in sexual activity within 8 to 9 days from the induction of the hyperprolactinemic state. The similarity in pattern and time to onset of behavioral suppression in pituitary-grafted and oPRL-treated animals suggests that behavioral deficits observed in animals with pituitary grafts result from chronic elevation of serum PRL levels.
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U2 - 10.1016/0018-506X(85)90012-1
DO - 10.1016/0018-506X(85)90012-1
M3 - Article
C2 - 4007795
AN - SCOPUS:0021883890
SN - 0018-506X
VL - 19
SP - 111
EP - 121
JO - Hormones and Behavior
JF - Hormones and Behavior
IS - 2
ER -