Pearson P L, Anderson L L, Jacobson C D
Department of Veterinary Anatomy, Iowa State University, Ames 50011, USA.
Brain Res Dev Brain Res. 1996 Apr 30;92(2):125-39. doi: 10.1016/0165-3806(95)00201-4.
Galanin (GAL) is a neuropeptide found in the mammalian brain and is involved in numerous functions including the control of feeding, growth and reproduction, and therefore may be an important peptide to study in agricultural species. We describe the immunohistochemical localization of GAL throughout prepubertal development in the Meishan pig, a Chinese breed known for its superior reproductive characteristics, but slow growth rate and abundant adipose tissue. Brains of animals from gestational day (g) 30, 50, 70, 90 and 110 and postnatal day (pn) 1, 10, 20 and 50 (duration of pregnancy averaged 114 days) were processed using a standard immunohistochemical technique utilizing a commercially available rabbit anti-porcine GAL antibody. Galanin-like immunoreactivity (GAL-IR) in cell bodies and fibers was evident in the brain at g30, primarily in the hypothalamus. Throughout prenatal development, cell bodies containing GAL-IR generally increased in number and distribution in the brain. During postnatal development, the number of cell bodies displaying GAL-IR decreased, particularly in hypothalamic areas. The distribution of GAL-IR in fibers became more widespread throughout gestational development, showing a pattern by pn1 that continued during later postnatal ages. The intensity of GAL-IR in fibers also increased throughout gestation. Some additional increases in immunoreactivity occurred postnatally, especially in the periventricular hypothalamus. The results of this study indicate that the distribution of GAL-IR in cell bodies and fibers in the Meishan pig brain was similar to that seen in other species, including the rat. These results support the hypothesis that GAL participates in the control of feeding, growth and reproduction in the pig.
