Novel function of recombinant pituitary adenylate cyclase-activating polypeptide as stimulator of innate immunity in African catfish (Clarias gariepinus) fry

Pituitary adenylate cyclase-activating polypeptide (PACAP): A regulator of the innate and acquired immune functions in juvenile fish

“…Recently, we have demonstrated that administration of recombinant C. gariepinus PACAP in fish at the larval stage not only promotes growth but also increases lysozyme and nitric oxide synthase (NOS)-derived metabolites. PACAP also modulated the antioxidant defense mechanisms [15]. In the present study, we found that PACAP produced an increase in serum lysozyme concentration correlated with its effect in body weight increment in both, juvenile C. gariepinus and O. niloticus.…”

“…Five micrograms of total RNA from peripheral blood leucocytes or head kidney and 1 ml of oligo (dT) 15 (0.5 mg ml À1 ) were incubated at 70 C for 5 min and placed on ice. The reaction was carried out in a total volume of 20 ml with 1X Avian Myeloblastosis Virus (AMV)-RT buffer, 1 mM of each dNTP, 1 unit ml RNase inhibitor, and 15 u mg À1 of AMV-Reverse Transcriptase (Promega, USA), incubated at 42 C for 30 min and at 95 C for 5 min and then diluted to a final volume of 100 ml in nuclease free water.…”

“…The published in-vivo studies on PACAP action in fish have been concerned with reproduction [8,9], brain development [10] and feeding behavior [11e14]. Very recently, our research group demonstrated that administration of recombinant Clarias gariepinus PACAP by immersion baths not only promotes growth but also increases lysozyme, nitric oxide-derived metabolites and antioxidant defenses (catalase and reduced glutathione) in fish larvae [15].…”

Evidence of a reproduction-related function for pituitary adenylate cyclase-activating polypeptide-related peptide in an Anabantidae fish

“…A recent study in the African catfish fry has shown that recombinant PRP enhanced growth promotion, as well as increasing the total protein concentration (Carpio et al 2008). This ability may be related to the effect of GHRH on pituitary GH, inducing protein synthesis and growth, which has been widely studied in teleosts.…”

Differential expression pattern of pituitary adenylate cyclase-activating polypeptide (PACAP) alternative splicing variants and its receptors in the immune system of rainbow trout (Oncorhynchus mykiss)

“…Little is known about PACAP tissuespecific expression related to its function in the immune system in teleost, which seems to be mainly immunostimulatory [20,21]. Recently, we have reported for the first time PACAP immunoreactivity and mRNA expression in isolated peripheral blood leucocytes from African catfish (Clarias gariepinus) and Nile tilapia (Orechromis niloticus) [21].…”