Lysipressin (Lypressin)

A multigene family for the vasopressin-like hormones? Identification of mesotocin, lysipressin and phenypressin in Australian macropods

Mesotocin ([Ile8]-oxytocin), lysipressin ([ Lys8]-vasopressin) and phenypressin ([Phe8]-vasopressin) have been identified in the western gray kangaroo (Macropus fuliginosus) as well as four other macropodids. Lysipressin and phenypressin, which differ by the amino acids in positions 2 (Tyr/Phe) and 8 (Lys/Arg) are likely products of two separate vasopressin-like genes. It is assumed that arginine vasopressin found in most mammals is the product of two identical genes which can be revealed in some species by differential mutations as seen usually in marsupials. The duality can also be revealed by differential mutations in another domain of the precursors, such as the neurophysin (MSEL-neurophysin), as observed in the ox.

Two multigene families for marsupial neurohypophysial hormones? Identification of oxytocin, mesotocin, lysipressin and arginine vasopressin in the North American opossum (Didelphis virginiana)

Oxytocin, mesotocin ([Ile8]-oxytocin), lysipressin ([Lys8]-vasopressin) and arginine vasopressin have been identified in the North American opossum (Didelphis virginiana) by amino acid composition and high pressure liquid chromatography. The same peptides with the exception of mesotocin have previously been found in two South American opossums (Didelphis marsupialis and Philander opossum). Although a dual heterozygocity could also explain the simultaneous presence of oxytocin/mesotocin on one hand, lysipressin/arginine vasopressin on the other, it is assumed, from the results obtained with individual glands of Australian and South American marsupials, that distinct genes encode for the four peptides.

Dual duplication of neurohypophysial hormones in an Australian marsupial: mesotocin, oxytocin, lysine vasopressin and arginine vasopressin in a single gland of the northern bandicoot (Isoodon macrourus)

Neurohypophysial hormones of an Australian marsupial, the Northern bandicoot (Isoodon macrourus), have been identified by their retention times in high-pressure reverse-phase liquid chromatography using two solvent systems and by their molar pressor or uterotonic activities. Two pressor peptides, arginine vasopressin and lysipressin, and two uterotonic peptides, mesotocin and oxytocin, have been characterized. Because mesotocin and arginine vasopressin have been identified in three other Australian marsupial families, it is assumed that a duplication of each ancestral gene occurred in Peramelidae and subsequent mutations in one copy led to the additional oxytocin and lysipressin. A similar dual duplication of neurohypophysial hormones has previously been discovered in the North-American opossum (Didelphis virginiana) so that the duplication propensity seems peculiar to marsupials in contrast to placental mammals.

The distribution of lysine vasopressin (lysipressin) in placental mammals: a reinvestigation of the Hippopotamidae (Hippopotamus amphibius) and Tayassuidae (Tayassu angulatus) families

The neurohypophyseal hormones of the hippopotamus (Hippopotamus amphibius) and collared peccary (Tayassu angulatus) were isolated by molecular sieving and preparative high-pressure liquid chromatography (HPLC). Oxytocin and arginine vasopressin have been identified by their amino acid compositions and their retention times in HPLC. Lysipressin (lysine vasopressin) was not detected in posterior pituitaries of two hippopotami and nine peccaries (less than 2% of arginine vasopressin in molar ratios). Among the suborder Suiformes of Artiodactyla, the families Hippopotamidae and Tayassuidae do not seem to possess lysipressin, in contrast to the family Suidae in which the pig has lysipressin in place of arginine vasopressin.