To test the hypothesis that maternal glucose restriction (GR) would compromise small intestine (SI) growth and development, we used a diet induced model of IUGR. Pregnant rats and offspring were fed isoenergetic diets {0% (deficient), 12, 24% (restricted), 60% (adequate) glucose) from gestation day (gd) 0 through adolescence. SI tissue was collected at gd20, birth, 12--24h, postnatal day (pd) 7, 15, 21, 28, 35, 49 and in controls. GR affected pup weight at early timepoints, resulting in IUGR; beyond effects due to differences in body wt, GR compromised SI length at 12--24h and promoted SI growth during peak lactation (pd15; total and distal wts). Dietary glucose regulated in utero (gd20) expression of sodium-dependent glucose co-transporter (SGLT1) protein. Diet-induced precocious maturation of lactase and sucrase was observed in glucose deficient animals. In summary, there were periodic but no permanent effects of dietary glucose intake on gut growth and development.

To test the hypothesis that maternal dietary glucose restriction throughout pregnancy and lactation would perturb glucose transporter (GLUT) protein levels in offspring, isoenergetic diets containing graded levels of glucose (0, 12, 24 and 60%) were fed to pregnant rats and their offspring from gestation day (gd) 0 through postnatal day (pd) 49. Diets were defined as deficient (0%), restricted (12, 24%) or adequate (60%) in glucose. Plasma, small intestine, liver and kidney tissues were collected perinatally (gd20, birth, 12--24hrs postnatal), during lactation (pd7, 15, 21), post-weaning (pd28, 35, 49) and in adult controls. The proximal and distal regions of the small intestine responded differently to the dietary glucose restriction. Proximal small intestine GLUT2 protein levels did not change throughout postnatal development and remained unaltered with dietary glucose restriction, while distal small intestine GLUT2 protein expression changed throughout postnatal development and with dietary glucose restriction. These findings, together with information from the literature, indicate a dissociation between small intestine GLUT2 mRNA expression, GLUT2 protein levels and small intestine glycogen reserves.

No description available.

No description available.

During adolescence, animals leave the natal home and interact with potentially threatening stimuli (i.e. stressors), e.g. unfamiliar environments and conspecifics. Adolescent stressors can result in fewer interactions with unfamiliar stimuli in adulthood, plausibly due to sustained effects of glucocorticoid exposure on stress physiology (e.g. glucocorticoid secretion and receptor expression). The current thesis tested the hypothesis that adolescent glucocorticoid exposure and social experiences act as stressors by quantifying the effects of the adolescent experiences on behavioural responses to unfamiliar stimuli and the underlying neuroendocrine mechanisms when in adulthood using two captive species, zebra finches and rats. In study one, adolescent zebra finches were dosed with the glucocorticoid corticosterone. In adulthood, birds dosed with corticosterone in early adolescence took longer to enter an unfamiliar environment when tested individually and had lower expression of the glucocorticoid receptor GR in the hippocampus and hypothalamus, brain regions that regulate stress responses. Glucocorticoids therefore appear to be an endocrine mechanism behind the long-term effects of adolescent stress. Subsequent studies explored whether higher social density and more unfamiliar social interactions during adolescence act as stressors. In study two, early adolescent zebra finches were housed in groups varying in conspecific number and density. In adulthood, females raised in larger groups secreted a higher stressor-induced corticosterone concentration and, if raised at lower density, spent more time in an unfamiliar environment when group housed. In study three, adolescent female rats were housed in familiar pairs or exposed to unfamiliar conspecifics. Unfamiliar adolescent interactions had no effects on responses to unfamiliar environments or stress physiology in adulthood, but heightened ultrasonic call rates. In this thesis, adolescent social experiences do not act like stressors, but modulate (especially female) social behaviour. Adolescent stressors and social experiences therefore have distinct effects on responses to unfamiliar stimuli and stress physiology that are maintained into adulthood.

Orientadores: Francisco Eduardo Martinez, Wilson de Mello Junior / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T19:05:57Z (GMT). No. of bitstreams: 1 Amorim_JoaoPaulodeArruda_D.pdf: 2245143 bytes, checksum: bd9c0e5b7bbf28b1db52dc1544fc418b (MD5) Previous issue date: 2012 / Resumo: Estudos realizados com mães dependentes de etanol demonstraram que elas apresentam maior dificuldade em cuidar de suas crianças, quando comparadas às mães não dependentes, evidenciando um distúrbio no comportamento materno durante o período pós-natal, que corresponde ao período onde as primeiras ligações sociais do animal são formadas e o organismo está muito sensível aos efeitos de estímulos ambientais. Vários estudos têm documentado as conseqüências do uso de etanol durante a gestação para a saúde do infante, porém pouca atenção tem sido dada à relação materno-infantil em mulheres alcoólicas durante o período pós-natal e as consequências dessa relação para prole feminina na vida adulta. O presente trabalho teve o objetivo de caracterizar o comportamento materno das ratas da variedade consumidora de etanol (UChA e UChB) e verificar as influências da variação do comportamento materno no desenvolvimento físico, na função reprodutiva e no status hormonal da prole feminina. O comportamento foi avaliado observando os seguintes parâmetros: carregar, lamber, amamentar com o dorso arcado e lamber, amamentar com o dorso arcado, amamentar passivamente e não contato com a prole. A avaliação do desenvolvimento físico da prole feminina considerou o dia do nascimento dos pêlos, da abertura dos olhos e do descolamento de orelhas. Para avaliar o desenvolvimento sexual inicial foram analisados os dias da abertura vaginal e idade do primeiro e segundo estro. A função reprodutiva foi avaliada pela regularidade de ciclo estral, pela expressão dos receptores AR, ER-? e ER-? no ovário e pelo perfil hormonal da prole feminina (níveis plasmáticos de FSH, LH, 17?-estradiol, progesterona e corticosterona). As fêmeas UChA apresentaram maiores frequências dos comportamentos de carregar, de lamber/limpar e de amamentar os filhotes. Mães muito cuidadosas apresentaram concentrações elevadas de corticosterona e 17?-estradiol. A prole UChA apresentou maior ganho de peso corporal, aceleração da abertura dos olhos, da abertura vaginal, da instalação da puberdade e sincronização do ciclo estral. A prole feminina que recebeu baixo cuidado materno (UChB) revelou maior duração do ciclo estral, aumento das concentrações de corticosterona e 17?-estradiol e de seus receptores ovarianos (ER-? e ER-?), maior peso dos ovários, maior número de folículos primordiais, antrais e maduros e mais imunomarcações positivas do Ki67 nos folículos ovarianos. Concluímos que a variedade de ratas UChB, apresenta acentuada variação do comportamento materno, sendo classificada como mãe pouco cuidadosa e essa variação do cuidado materno afeta diretamente o desenvolvimento físico, a instalação da puberdade, os níveis hormonais, desregula o ciclo estral e a foliculogênese e regula diferencialmente a expressão dos receptores ER-? e ER-? nos ovários de ratas adultas / Abstract: Studies focused on drug-dependent mothers (mainly ethanol-dependent mothers) have demonstrated that there is an enormous difference in the care of their children compared to non-dependent mothers, showing an disorder in maternal behavior during the postnatal period, which corresponds to the period where the first social bonds are formed and the animal's organism is very sensible to the effects of environmental stimuli. Various studies have documented the consequences of ethanol use during pregnancy for the health of the infant, but little attention has been given to the mother-child relationship in alcoholic female during the postnatal period and the consequences of this relationship to female offspring in adulthood. The aim of the present work is to evaluate maternal care in ethanol-preferring rats (UChA and UChB) and its effects on physical development, in sexual function and in status hormones in female offspring. The behavior was evaluated by observing the following parameters: carry, licking/grooming, arched-back nursing and licking/grooming, arched-back nursing, passive nursing, contact and not with the pups. The evaluation of the physical development of the female offspring considered the day of birth of hair, eye opening and detached ears. To evaluate the early sexual development were analyzed days of vaginal opening and age of first and second estrous. The reproductive function was evaluated by the regularity of the estrous cycle, the expression of receptors AR, ER-? and ER-? in the ovary and the hormonal status of female offspring (plasma levels of FSH, LH, 17?-estradiol, progesterone and corticosterone). UChA mothers showed higher frequencies of carrying, licking/grooming and nursing the pups. Mothers high care evidencing the highest plasma corticosterone levels and 17?-estradiol. The UChA offspring showed greater body weight gain, accelerated eye opening, vaginal opening, the installation and synchronization of estrous cycle. The female offspring who received low maternal care (UChB) showed an increase of the estrous cycle, concentrations of corticosterone and 17?-estradiol and ovarian receptors (ER-? and ER-?, higher ovarian weight and increased number of primordial, antral and mature follicles and higher Immunoreactivity for Ki-67 in the ovarian follicles. We conclude that UChB rats show marked variations in maternal care, being classified as low maternal care and the variation of maternal care directly affects the physical, the installation of puberty, hormone levels, deregulate the estrous cycle and folliculogenesis and differentially regulates the expression of receptors ER-? and ER-? in the ovaries of adult rats / Doutorado / Anatomia / Doutor em Biologia Celular e Estrutural