Expression profile of the pore-forming subunits α1A and α1D in the fetal bovine hypothalamus: a mammal with a long gestation.

This study describes the expression of the voltage operated calcium channels (VOCCs) subunits alpha 1A (typical of the P/Q family) and alpha 1D (of the L family) in the bovine hypothalamus. The expression of both P/Q and L families has been characterized in the brain of adult mammals. However, their distribution and expression during foetal neuronal differentiation have not yet been determined. The expression profile of the alpha 1A and alpha 1D pore-forming subunits was investigated during four embryonic stages in bovine foetuses. Our data suggest that the expressions of alpha 1A and alpha 1D are correlated during development, with an increase only in males that peaks on the last period of gestation. Bovine male hypothalami showed significantly higher alpha 1A and alpha 1D expression values in comparison to female ones during the whole developmental period. In the females, the expression profiles of both genes were constant during all the developmental time. Immunohistochemical studies confirmed the presence of the alpha 1A and alpha 1D protein subunits in foetal hypothalamic neurones starting from the third foetal stage. Our data provide new information on the hypothalamic expression of alpha 1A and alpha 1D subunits during development in a mammal with a long gestation period and a large and convoluted brain. (C) 2013 Published by Elsevier Ireland Ltd.