Mannelli Publications

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Psych Cents

Publications

1: Life Sci. 1987 Oct 19;41(16):1881-4. Links

Neurotransmitters and their metabolites in the brains of fetal and newborn lambs.

Richards GE,
Gluckman PD,
Mannelli SC.

Department of Pediatrics, University of Texas Medical Branch, Galveston.

We tested the hypothesis that there is an orderly progressive increase in neurotransmitters in the brains of fetal and neonatal sheep. The pregnant ewes or newborns were killed with an intravenous overdose of pentobarbitone. Brains were removed immediately and frozen at -80 degrees C for later dissection and measurement of norepinephrine (NE), dopamine (DA), serotonin (5HT), homovanillic acid (HVA) and hydroxyindole acetic acid (HIAA). Fetuses were studied at 130-135 days gestation (term gestation 147 days), 140-145 days gestation and 1-5 days after birth. The only compound that was significantly different at the three ages was HIAA. Significant regional differences for NE, DA, and HVA, but not for 5HT were demonstrated.

PMID: 2443785 [PubMed - indexed for MEDLINE]

1: J Dev Physiol. 1990 Dec;14(6):331-6. Links

Expanded ontogeny of neurotransmitters and their metabolites in the brains of fetal and newborn lambs.

Department of Pediatrics, University of Texas Medical Branch, Galveston.

To evaluate the ontogeny of the brain neurotransmitters norepinephrine, dopamine, serotonin and the metabolites hydroxyindoleacetic acid and homovanillic acid, we measured these neurotransmitters in 10 brain areas at three ages in fetal sheep and two ages in newborn lambs. Norepinephrine exhibited an increase only at 25-30 days after birth in the midbrain, lateral hypothalamus, dorsal medial hypothalamus and ventral medial hypothalamus. Dopamine concentration was very low and did not change over the ages examined. Homovanillic acid decreased after 125 days in the cerebellum, but this change is probably not biologically meaningful, since there were no statistically significant changes in homovanillic acid in other brain areas. Serotonin increased at 25-30 days after birth in the ventral medial hypothalamus, but changes in other brain areas were not significant. Hydroxyindoleacetic acid reached its greatest concentration at 1-5 days after birth in nine of the ten brain areas examined. Thus we conclude that the serotonin system is undergoing more change in the last third of gestation and first month of extrauterine life than the norepinephrine or dopamine systems.

PMID: 1713933 [PubMed - indexed for MEDLINE]

Changes in selected brain neurotransmitters and their metabolites in the lamb after thyroidectomy during the last two trimesters of gestation or the early neonatal period.

Pediatr Res. 1990 Nov ;28:469-72 1979436

Changes in selected brain neurotransmitters and their metabolites in the lamb after thyroidectomy during the last two trimesters of gestation or the early neonatal period.

G E Richards , P D Gluckman , K Ball , S C Mannelli , J A Kalamaras

To evaluate in a development context the effect of congenital hypothyroidism on concentrations of the neurotransmitters norepinephrine, dopamine, and serotonin (5HT) in selected brain areas of the ovine fetus, we studied the effect of thyroidectomy at three ages on the concentrations of these neurotransmitters and their major metabolites, homovanillic acid and 5-hydroxyindoleacetic acid. Fetuses underwent thyroidectomy at 90-95 or 105-115 d gestation (term = 147-150 d) or 1-5 d after birth. Approximately 25 d after thyroidectomy, at d 120-125 or 130-135 of gestation or 25-30 d after birth, respectively, the ewes were killed and fetal brains removed. Neurotransmitters and their metabolites were measured by HPLC with electrochemical detection. Thyroidectomy in the 2nd trimester increased 5HT in five brain areas: anterior hypothalamus, dorsal medial hypothalamus, pons, medulla, and cerebellum. Thyroidectomy in the 3rd trimester increased 5HT in the pons and medulla, increased norepinephrine in the dorsal medial hypothalamus and pons, and increased homovanillic acid in the posterior hypothalamus. Thyroidectomy in the newborn period decreased NE in the anterior hypothalamus, ventral medial hypothalamus, and midbrain, decreased 5-hydroxyindoleactic acid in the posterior hypothalamus, lateral hypothalamus, dorsal medial hypothalamus, and ventral medial hypothalamus, and decreased homovanillic acid in the dorsal medial hypothalamus and ventral medial hypothalamus. From these data we conclude the following: 1) Hypothyroidism causes changes in neurotransmitter concentrations only in selected brain areas of the ovine fetus, rather than causing generalized and similar changes in all brain areas; and 2) 5HT 5-hydroxyindoleacetic acid concentrations are affected more often than the other neurotransmitters evaluated, perhaps because the 5HT neurotransmitter system is developing at these times.

Mesh-terms: Animals; Animals, Newborn; Brain, metabolism; Female; Fetus, metabolism; Gestational Age; Hypothyroidism, congenital; Hypothyroidism, metabolism; Neurotransmitters, metabolism; Pregnancy; Sheep; Support, Non-U.S. Gov't; Support, U.S. Gov't, P.H.S.; Thyroidectomy;

http://www.tamug.tamu.edu/prospect/Catalog/CAT985.htm

MANNELLI, SANDRA C., Lecturer in Oceanography (Chemistry Laboratory) (1989-97). B.S., Texas A&M University, 1983; M.A., University of Houston-Clear Lake, 1986.

Dissertation: University of Houston

12

3122354

Case study: The workings of an alternative education program for at-risk Hispanic students

Mannelli, Sandra Carol

Ed.D, University of Houston, 2004