Scopolamine modulates paternal parental retrieval behavior in mice induced by the maternal mate.

Appropriate parental care by the father can greatly facilitate healthy human family life. Much less is known from animal studies about the factors leading to paternal parental care than those favoring maternal parent care. Recently, we have reported that sires of the ICR strain of laboratory mice can express maternal-like retrieval behavior when separated from their pups through ultrasound and pheromonal signals from the dam, i.e. mate-dependent parental care. The sire's retrieval behavior was inhibited by prior treatment of scopolamine, a muscarinic cholinergic inhibitor, and recovered by physostigmine. KCNQ K(+)-channel blocking and enhancing drugs, linopiridine and retigabine, were also examined. Linopiridine alone did not enhance care after pairing with the dam, nor change scopolamine-induced inhibition of care. Retigabine totally suppressed parental care, and this effect was partially rescued by co-administration of linopiridine. These results indicate the involvement of cholinergic cellular signaling in the central nervous system in the maternal induction of paternal parental behavior in ICR mice.