Both particular myocardial locations in the human heart and the canonical transient
receptor potential 6 (TRPC6) cation channel have been linked with cardiac pathophysiologies. Thus,
the present study mapped TRPC6-protein distribution in select anatomic locations associated with
cardiac disease in the context of an orienting pathological assessment. Specimens were obtained
from 5 body donors (4 formalin fixation, 1 nitrite pickling salt-ethanol-polyethylene glycol (NEP)
fixation; median age 81 years; 2 females) and procured for basic histological stains and TRPC6-
immunohistochemistry. The latter was analyzed descriptively regarding distribution and intensity
of positive signals. The percentage of positively labelled myocardium was also determined (optical
threshold method). Exclusively exploratory statistical analyses were performed. TRPC6-protein was
distributed widespread and homogenously within each analyzed sample. TRPC6-immunoreactive
myocardial area was comparable regarding the different anatomic regions and sex. A significantly
larger area of TRPC6-immunoreactive myocardium was found in the NEP-fixed donor compared
to the formalin fixed donors. Two donors with more severe heart disease showed smaller areas of
myocardial TRPC6-immunoreactivity overall compared to the other 3 donors. In summary, in the
elderly, TRPC6-protein is widely and homogenously distributed, and severe cardiac disease might be
associated with less TRPC6-immunoreactive myocardial area. The tissue fixation method represents
a potential confounder