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Altered cardiovascular haemodynamics and baroreceptor-heart rate reflex in adult sheep after prenatal exposure to dexamethasone


, : Altered cardiovascular haemodynamics and baroreceptor-heart rate reflex in adult sheep after prenatal exposure to dexamethasone. Clinical Science 97(1): 103-109

Numerous epidemiological studies, together with mounting evidence from studies in animals, point to a correlation between an adverse intrauterine environment and the early onset of cardiovascular and metabolic diseases later in life. We were the first to show that sheep exposed to dexamethasone (0.28 mgcntdotkg-1cntdotday-1 for only 2 days) at the end of the first month of pregnancy (PTG1), but not those exposed at the end of the second month of pregnancy (PTG2), had a higher basal mean arterial pressure (MAP) 19 months after birth. In the present study we report the MAP, cardiovascular haemodynamics and baroreflex sensitivity in these animals at 40 months of age. MAP in the PTG1 group was significantly higher than in the control group (91+-1 mmHg and 81+-1 mmHg respectively; P < 0.001) and also when compared with the PTG2 group (82+-1 mmHg; P < 0.001). There was a significant increase in cardiac output in the PTG1 group compared with the control group (108+-2 and 96+-4 mlcntdotmin-1cntdotkg-1 respectively; P < 0.05). The increase in cardiac output in the PTG1 group was due to an increase in stroke volume (1.82+-0.08 mlcntdotkg-1cntdotbeat-1, compared with 1.46+-0.06 mlcntdotkg-1cntdotbeat-1 in the control group; P<0.05), but not in heart rate. In the hypertensive group of animals (PTG1), there was a rightward shift of the baroreflex curve. In group PTG2 (the normotensive group of animals), a lower gain was found before and during propranolol treatment. The decrease in gain of the baroreflex was not associated with changes in heart rate range, suggesting an impairment in the central processing of the baroreceptor signals. Thus sheep fetuses exposed to dexamethasone for only 2 days at the end of the first month of gestation have high blood pressure (dependent upon the increase in cardiac output) and a reset of the baroreflex at 40 months of age. Animals that have received prenatal dexamethasone closer to mid-gestation, although normotensive with normal cardiac output, showed analtered baroreceptor-heart rate response.

US$19.90

PMID: 10369801

DOI: 10.1042/cs0970103


Other references

Tian W H., 1982: Uptake and retrograde axonal transport of horseradish peroxidase injected into botulinum toxin poisoned muscle in rats. The quantity of HRP [horseradish peroxidase] in sciatic nerve and both ventral and dorsal roots of [lumbar] L4-6 spinal segments of rats was determined by the coupled oxidation reaction method. Little endogenous peroxidase was found in normal nerv...

Xavier,M.O.; Meinerz,A.R.M.; Cleff,M.B.; Osorio,L.G.; Schuch,L.F.D.; Nobre,M.O.; SilvaFilho,R.P.; Meireles,M.C.A., 2008: Chlorexidine-cetrimide efficacy in ambient disinfection against Aspergillus spp. The study evaluated the efficacy of chlorhexidine-centrimide for the environmental control of <i>Aspergillus</i> spp. in marine animals, with special consideration of the influence of climate and population variations. Air samples were...

Lucht W., 1985: Isorhipis marmottani new record for germany coleoptera eucnemidae. Entomologische Blaetter fuer Biologie und Systematik der Kaefer 81(1-2): 91-94

Rech, R.R.; Halpern, R.; Tedesco, A.; Santos, D.F., 2013: Prevalence and characteristics of victims and perpetrators of bullying. To determine the prevalence of bullying (victims and perpetrators) in a representative sample of sixth graders from schools located in the city of Caxias do Sul, RS, Brazil and to determine possible associations with maternal education, socioecono...

Han, S.Hoon.; Lee, J.Won.; Hyun, C.Lim.; Yoo, S.Yeon.; Lee, J.Hoo.; Kwon, J.Mi.; Kim, W.Kun., 2012: Solitary rectal metastasis from primary small cell lung carcinoma. Lung cancer may rarely appear with a solitary rectal metastasis and no other metastases. We report the first case of primary small cell lung cancer presenting with a solitary rectal metastasis in a 62-year-old man. Chest computed tomography reveal...

Maletskii, S.; Zhumabekov, E., 1974: Inheritance of incompatibility in the sugarbeet (Beta vulgaris L.). analysis of incompatibility in first-generation hybrids. Soviet genetics: (Transl 1976), 10 (8) 1062-1064

Eliseev, B.; Kryuchkova, P.; Alkalaeva, E.; Frolova, L., 2011: A single amino acid change of translation termination factor eRF1 switches between bipotent and omnipotent stop-codon specificity. In eukaryotes a single class-1 translation termination factor eRF1 decodes the three stop codons: UAA, UAG and UGA. Some ciliates, like Euplotes, have a variant code, and here eRF1s exhibit UAR-only specificity, whereas UGA is reassigned as a sens...

Lagutina, M.V., 1981: Functional activity of circulating neutrophils in infectious hepatitis in children. Pediatriia: 20-21

Perez-Valdivieso, J.Ramon.; Monedero, P.; Vives, M.; Garcia-Fernandez, N.; Bes-Rastrollo, M.; del Campo, A.García.; i García-Campomanes, F.Roma.; Fernández, A.Torrents.; Cuello, X.Peris.; González, M.Carrasco.; Perez, R.Hinojosa.; Aviles, A.Herruzo.; Gómez-Luque, A.; Navarro, M.Rubio.; Garagarza, Jé.María.San.Jose.; Palacios, V.Burgos.; Martinez, N.Royuela.; Barrios, Jé.M.; Hortal, J.; Lago, E.Novoa.; Candela, A.; Elías, E.; Martín, Aón.; Porta, J.; Vela, A.; Vicente, Jé.Luis.; Suare, 2009: Cardiac-surgery associated acute kidney injury requiring renal replacement therapy. A Spanish retrospective case-cohort study. Acute kidney injury is among the most serious complications after cardiac surgery and is associated with an impaired outcome. Multiple factors may concur in the development of this disease. Moreover, severe renal failure requiring renal replacemen...

Klinkhoff, A.V.; Teufel, A., 1993: Management of rheumatoid arthritis with very low dosage of IM gold. Arthritis & Rheumatism 36(9 SUPPL ): S112