M C Mcnamara

Learn More
The effect of lysine vasopressin on the performance of young-adult and old rats subjected to a conditioned flavor aversion procedure was studied. Young rats maintained an aversion to a 0.1% saccharin solution significantly longer than did older rats. Treatment with lysine vasopressin ( 1 microgram/kg) during the recovery period prolonged the aversion in(More)
Treatment with the serotonin (5-HT) reuptake inhibitor zimelidine, 20 mg/kg/24 hr, SC, for 14 days increased the duration of vaginal cycles in 3 month-old Long Evans hooded rats. It induced persistent vaginal estrus in 12 of 16 ten-month-old animals, and blocked reinitiation of vaginal cycles by L-dopa in 10 of 10 twenty-month-old rats. A single injection(More)
Microdissected areas of the rabbit brain were isolated at prenatal day E-29, postnatal days P-3, 7, 14, 21, 2 months and adults. Methionine-enkephalin (ME) was assayed by RIA and ME concentration [ME] was expressed relative to the protein content of the extracted brain tissues. In brain nuclei with important roles in respiratory control [ME] was higher in(More)
The present immunocytochemical study demonstrates serotonin (5-HT) depletion in the dorsal raphe nucleus (DRN) of 3- and 21-day-old rabbits following exposure to mild (10% ambient partial pressure of oxygen) and severe hypoxia (5% ambient oxygen). Under the mild hypoxic condition, 5-HT immunoreactivity in cells and fibers of the DRN was decreased in(More)
To examine the development of daily variations in norepinephrine levels, norepinephrine concentrations were measured within five distinct brainstem regions in 3-day-old, 21-day-old, and adult rabbits at 6-h intervals throughout the day. Norepinephrine was measured by radioenzymatic assay, and norepinephrine concentration was expressed relative to wet tissue(More)
To examine the development of daily variations in dopamine levels, we measured dopamine concentrations within five distinct brainstem regions in 3- and 21-day-old, and adult rabbits at 09.30, 15.30, 21.30 and 03.30 h. Dopamine was measured by radioenzymatic assay and the dopamine concentration was expressed relative to wet tissue weight. In addition to(More)
By use of a microtechnique and sensitive enzymatic isotopic assays norepinephrine (NE), dopamine (DA) and serotonin (5-HT) turnover rates were measured in 6 discrete brainstem regions. The results from young (3 days) and adult (1 year) rabbits were compared. In the dorsal raphe nucleus (dr) of the younger animals the slopes of disappearance of NE and 5-HT(More)