Comparative analysis of storage tissue and insulin-like neurosecretion in diploid and triploid mussels Mytilus galloprovincialis LMK in relation to their gametogenesis cycle

We conducted a comparative stereological analysis of diploid and induced triploid Mytilus galloprovincialis germinal and storage tissue volume fractions along an annual cycle, concomitantly to the irnmunocytochemical study of cerebral insulin-like peptide (ILP) secretion. Germinal tissue developed to the same extent in diploids and triploids, while storage tissue disappeared with the same pattern in both populations. We present irnrnunocytochemical evidence of an ILP cycle for the first time in bivalves. Moreover, this cycle is closely related to gametogenesis and storage tissue cycles and presents the same features in diploid and triploid animals.