ESR1 and ESR2, classic nuclear receptors of oestrogen signalling, are expressed by human AF [13] and NP cells, which was confirmed in the present work for the bovine cells, and their expression was shown to be significantly decreased in the NP with the aggravation of IVDD both in samples from male and female patients [39,40]. The gene discussed is ESR1; the disease is atrial fibrillation.