PMC

Dispersed pituitary cell number in randomly cycling wild-type and mutant females (control) and after 3 weeks of estradiol-17β treatment (estradiol). For all groups, n = 10. ∗∗, P < 0.01, ∗∗∗, P < 0.001 denotes levels of significance compared with wild-type controls.

Representative Western blot of activated STAT5: lane 1, positive control using lysate of T47-D breast cancer cell line; lane 2, size marker; lanes 3 and 4, wild-type anterior pituitary lysates with and without estradiol-17β (E2); lanes 5 and 6, mutant anterior pituitary lysates with and without estradiol-17β; n = 5.

Pituitary prolactin content in ng/pituitary (A) and circulating plasma prolactin in ng/ml (B) of randomly cycling wild-type and mutant females (denoted control), a second group of randomly cycling wild-type and mutant females treated for 3 weeks with estradiol-17β treatment (estradiol), and thirdly, another group of wild-type and mutant females seven days postpartum. n = 10 for all groups. ∗, P < 0.05, ∗∗, P < 0.01, ∗∗∗, P < 0.001 denote levels of significance compared with the wild-type control group.

Carmine-stained whole mounts of the fourth inguinal mammary gland from 8-week-old virgin wild-type (Left) and mutant (Right) animals. Two representative glands are shown for each genotype. Formation of the ductal tree is in progress, with mitotic terminal end buds clearly visible at the ductal termini; there is reduced ductal branching in the mutants animals. The lymph node is seen as a darkly staining mass at the center of the photographs.

Pituitary prolactin message levels in arbitrary units, measured by Northern blotting of randomly cycling wild-type and mutant females (denoted control), a second group of randomly cycling wild-type and mutant females treated for 3 weeks with estradiol-17β treatment (estradiol) and thirdly, another group of wild-type and mutant females 7 days postpartum. Values were determined relative to glyceraldehyde-3-phosphate dehydrogenase as a control probe. For all groups, n = 5. ∗, P < 0.05 denote levels of significance compared with the wild-type control group. Two representative pituitary samples are illustrated for each group.

(A) Targeted disruption of the murine galanin gene. The targeting vector replaces the first five exons of the galanin gene with a Neo cassette in reverse orientation. HSV-TK denotes the herpes simplex thymidine kinase and Neo the neomycin resistance gene. A denotes the 5′ external probe. B, BamHI, Bg, BglII, E, EcoRI., (B) Identical results obtained by Southern hybridization (genomic DNA digested with BglII and probed with the 5′ external probe) and PCR screening on the same litter derived from a mating of two heterozygotes.