Summary of Immunostaining Results in Hamsters.

Host #: R = rabbit; GP = guinea pig. Peak Time: Hamsters were perfused at the time of expected peak of immunostaining and a series of dilutions was examined. Nadir Time: Hamsters were perfused at the expected low point of immunostaining rhythms (ZT0 for PER1, PER2, and ZT12 for BMAL1). CLOCK immunostaining was comparable at ZT0 and ZT12; dilution studies were conducted at ZT12 and results from ZT0 are listed arbitrarily as Nadir Time. Studies at nadir time used the antibody concentration found to give optimal labeling at the peak time. N = number of animals tested. Results are scored as Described in Table 1: −(no SCN cells labeled), +(relatively poor staining), ++(good staining in SCN), and +++(best staining of SCN cells compared to background). NS indicates non-specific staining (cells inside and outside the SCN were labeled with the same intensity). “n.d." indicates not determined.