NCBI Summary:
Hyperpolarization-activated cation channels of the HCN gene family, such as HCN1, contribute to spontaneous rhythmic activity in both heart and brain.[supplied by OMIM]
General function
Channel/transport protein
Comment
Cellular localization
Plasma membrane
Comment
Ovarian function
Comment
Expression regulated by
Comment
Ovarian localization
Oocyte, Granulosa, Theca, Luteal cells
Comment
The expression of hyperpolarization activated cyclic nucleotide gated (HCN) channels in the rat ovary are dependent on the type of cell and the reproductive age of the animal: a laboratory investigation. Yeh J et al. ABSTRACT: BACKGROUND: Aim of this study was to test the hypothesis that levels of hyperpolarization activated cyclic nucleotide gated channels 1 to 4 (HCN1-4) are linked to the reproductive age of the ovary. METHODS: Young, adult, and reproductively aged ovaries were collected from Sprague-Dawley rats. RT-PCR and western blot analysis of ovaries was performed to investigate the presence of mRNA and total protein for HCN1-4. Immunohistochemistry with semiquantitative H score analysis was performed using whole ovarian histologic sections. RESULTS: RT-PCR analysis showed the presence of mRNA for HCN1-4. Western blot analysis revealed HCN1-3 proteins in all ages of ovarian tissues. Immunohistochemistry with H score analysis demonstrated distinct age-related changes in patterns of HCN1-3 in the oocytes, granulosa cells, theca cells, and corpora lutea. HCN4 was present only in the oocytes, with declining levels during the reproduction lifespan. CONCLUSIONS: The evidence presented here demonstrates cell-type and developmental age patterns of HCN1-4 channel expression in rat ovaries. Based on this, we hypothesize that HCN channels have functional significance in rat ovaries and may have changing roles in reproductive aging.