Forebrain expression of c-fos due to active maternal behaviour in lactating rats

Variations in Nucleus Accumbens Dopamine Associated with Individual Differences in Maternal Behavior in the Rat

“…Mother-pup interactions in the rat are associated with in- creases in cFos-positive cells in the VTA (Lin et al, 1998) and n. Acc (Lonstein et al, 1998). Electrolytic (Galfori and Le Moal, 1979;Numan and Smith, 1984) or 6-hydroxydopamine (Hansen et al, 1991(Hansen et al, , 1993 lesions of the VTA or the n. Acc greatly disrupt maternal behavior.…”

Comparison of the “Nursing” and Other Parental Behaviors of Nulliparous and Lactating Female Rats

“…To compare mother-litter interactions in the presence and in the absence of suckling, pups interacting with lactating dams received either bilateral mystical pad injections of 0.02 ml of 2.5% lidocaine (Sigma, St. Louis, MO) dissolved in 0.9% saline or control injections of saline 10 min prior to testing. Mystacial pad anesthesia prevents the pups' ability to locate, adhere to, and suckle on a nipple, which greatly reduces the elicitation of kyphosis in their dam (Lonstein et al, 1998b;Lonstein and Stern, 1997a, b;Stern and Johnson, 1990). Perioral lidocaine injections do not, however, alter the activity and rooting behavior of the pups (Lonstein et al, 1998b) and dams display active maternal behaviors such as retrieval and licking toward the active but periorally anesthetized pups (Lonstein and Stern, 1997a, b;Stern and Johnson, 1990).…”

“…Mystacial pad anesthesia prevents the pups' ability to locate, adhere to, and suckle on a nipple, which greatly reduces the elicitation of kyphosis in their dam (Lonstein et al, 1998b;Lonstein and Stern, 1997a, b;Stern and Johnson, 1990). Perioral lidocaine injections do not, however, alter the activity and rooting behavior of the pups (Lonstein et al, 1998b) and dams display active maternal behaviors such as retrieval and licking toward the active but periorally anesthetized pups (Lonstein and Stern, 1997a, b;Stern and Johnson, 1990). To control for the perioral injections of the litters interacting with lactating dams, litters interacting with maternal virgins also received perioral injections of either lidocaine or saline (ns ϭ 7 and 8 litters, respectively) 10 min before testing.…”

“…This suggests differential sensory regulation of this posture in sensitized and lactating mothers. Under certain conditions, stimulation provided by active pups rooting in their dam's ventrum in search of a nipple produces cellular (Lonstein et al, 1998b;Xerri, Stern, and Merzenich, 1994), endocrine (Jakubowski and Terkel, 1986;Stern and Siegel, 1978), and behavioral consequences in female rats (Stern, 1991). Rooting by pups is not adequate, though, for maximal c-fos transcription within the cPAG or the elicitation of kyphosis in normal lactating dams (Lonstein and Stern, 1997a, b), but is apparently somewhat effective for eliciting kyphosis in sensitized virgins.…”

Functional Magnetic Resonance Imaging Shows Oxytocin Activates Brain Regions Associated with Mother–Pup Bonding during Suckling

“…Focal lesions of the medial preoptic area, bed nucleus of the stria terminalis, lateral septum, amygdala, cingulate cortex, nucleus accumbens, and substantia nigra have demonstrated their role in the onset and/or maintenance of maternal behaviors (Slotnick and Nigrosh, 1975;Numan and Corodimas, 1985;Numan and Numan, 1996;Stack et al, 2002;Li and Fleming, 2003;Numan and Insel, 2003). Using cellular markers of gene expression, a more intricate network comprising a number of cortical, thalamic, hypothalamic, limbic, and brainstem sites has been identified (Kendrick et al, 1997;Lin et al, 1998;Lonstein et al, 1998;Li et al, 1999). Many of these brain areas express moderate to high levels of oxytocin receptors (Tribollet et al, 1988;Yoshimura et al, 1993;Veinante and Freund-Mercier, 1997;Vaccari et al, 1998), suggesting a convergence of maternal and oxytocinergic pathways.…”