Seasonal variation in the phenotype of adult ferret (Mustela putorius furo) cremaster muscle

Abstract

Using immunocytochemistry, electrophoresis and immunoblotting, we studied the expression of fast and slow myosin heavy chain isoforms in adult ferret muscles during quiescent and breeding periods. Adult cremaster muscle expressed slow and fast myosin heavy chain in relatively similar amounts during the quiescent period. During the breeding period, the expression of slow myosin heavy chain, I, significantly decreased, and fast myosin heavy chain II, was predominant. No alteration of the MHC pattern in EDL and soleus muscles was detected between the quiescent and breeding periods. The possible involvement of androgens and mechanical factors in the regulation of myosin heavy chain expression in adult cremaster muscle is discussed.

Fiber Type Composition of the Muscle Responsible for Throat Fan Extension in Green Anole Lizards

“…Testosterone establishes the male-typical fiber composition in the mastication muscles of mice [Eason et al, 2000], guinea pigs [Gutmann et al, 1970;Lyons et al, 1986], and rabbits [English and Schwartz, 2002] during puberty, and in the laryngeal muscles of African clawed-frogs during metamorphosis [Sassoon et al, 1987;Catz et al, 1995]. Seasonal changes in contractile properties or fiber-types also occur in the fast calling muscles of the gray tree frog [Girgenrath and Marsh, 2003] and the ferret cremaster [Rouaud et al, 1996]. In male anoles, both testosterone levels and frequency of dewlap display decrease dramatically during the nonbreeding season [Jenssen et al, 1995Lovern et al, 2001], either of which might result in a change in ceratohyoideus fiber composition.…”

Effect of cyclopiazonic acid, an inhibitor of the sarcoplasmic reticulum Ca‐ATPase, on skeletal muscles from normal and mdx mice

“…Immunodetection of SERCA was performed using an anti-SERCA2a polyclonal antibody (1 : 100 in PBS) and an anti-SERCA1 monoclonal antibody (1 : 2 in PBS), kindly provided by Dr F. Wuytack (Eggermont et al 1990). The myofibre type was determined using an anti-slow myosin, heavychain monoclonal antibody (1 : 1000 in PBS; Rouaud et al 1996). Sections were incubated with primary antibodies at room temperature, washed in PBS, and re-incubated with a secondary antibody.…”