Pau K (2001) Immunolesioning of brainstem DBH neurons on the mating-induced LH and prolactin surge in the rabbit. Neuroscience 2001 Abstracts 466.7. Society for Neuroscience, San Diego, CA.
Summary: Coitus induces a surge release of norepinephrine (NE) that is accompanied by a preovulatory gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) surge. Prazosin, an alpha-1 adrenergic antagonist, attenuates the GnRH/LH surge, and tyrosine hydroxylase (TH) gene expression in brainstem NE areas increases within 30 min after coitus. Here, we determined the coitus-induced LH/prolactin surge after specific lesioning of dopamine beta-hydroxylase (DBH) neurons in the brainstem with monoclonal anti-DBH sera conjugated with the ribosomal cytotoxin saporin (DBH-SAP). Female NZW rabbits received 3rd cerebroventricular injection (Day 0) of either DBH-SAP (20 µg, n=4) or SAP (3 µg, n=4). On day 14, the four DBH-SAP females were paired with stud males, but none of them mated. After daily injection of estradiol benzoate (EB, 3 µg) for 3 days, all eight females mated. Blood samples were taken once before, and at 10-min intervals for 4 hours after, coitus. Brainstems were prepared for immunocytochemical detection of DBH and TH. Coitus increased both LH and prolactin release in either DBH-SAP or SAP animals. However, postcoital LH and prolactin levels were 55% lower and 50% higher, respectively, in DBH-SAP rabbits than in SAP animals. The number of DBH neurons was near zero in the A6 and reduced by 80% in the A1 and 70% in the A2 noradrenergic areas in DBH-SAP animals. The number of TH neurons was reduced by 95% and 30% in the A6 and A1 areas, respectively, and did not change in the A2 area. The results suggest that the presence of intact brainstem NE neurons are critical for sexual performance and production of normal LH/prolactin surge after coitus in female rabbits.
Related Products: Anti-DBH-SAP (Cat. #IT-03)