Archivos suplementarios
Palabras clave
neuronas
nidos artificiales
crías
Resumen
Las tortugas marinas son consideradas como amenazadas o en peligro de extinción. Debido a ello, se han establecido viveros a donde los huevos recién depositados por las hembras son trasladados e incubados en nidos artificiales como estrategia de conservación. A lo largo del tiempo, efectos negativos de la incubación artificial en las crías han sido documentados, sugiriendo que los factores fisico-químicos de los nidos artificiales pudieran ser la causa. Nuestra hipótesis es que los factores fisicoquímicos generan en el embrión/feto una exposición crónica al estrés durante la incubación artificial. Por lo tanto, el objetivo central del presente trabajo es evidenciar los efectos del traslado y la exposición crónica al estrés pre-eclosión en crías de L. olivacea recién eclosionadas, comparando la citología de algunas zonas cerebrales, hipófisis, glándula adrenal y gónada, así como la concentración de corticosterona, en crías nacidas en nidos artificiales o nidos naturales. La elección de los órganos se basa en evidencia proveniente de mamíferos que muestra que la exposición crónica al estrés durante etapas embrionarias modifica la arquitectuta de los circuitos neuronales conduciendo a alteraciones conductuales, cognitivas y reproductivas en respuesta a la sobreactivación del eje hipotálamo-hipofisiario-adrenal. Los resultados obtenidos hasta ahora en nuestro modelo experimental apoyan la hipótesis propuesta, debido a que los organismos eclosionados en nidos artificiales presentan un menor peso que los de nidos naturales, además sus hipófisis y glándulas adrenales presentan una mayor masa (datos que apoyan la sobreactividad del eje hipofisiario-adrenal). Por el contrario, se observó una disminución significativa en el peso de las gónadas. Los análisis estadísticos revelan que dichas diferencias son significativas. En cuanto a la citoarquitectura neuronal, tortugas eclosionadas de nidos artificiales tienen árboles dendríticos hipótroficos.Citas
Baldwin J, GE, M.K y Patak A. 1989. Anaerobic metabolism during dispersal of green and loggerhead turtle hatchlings. Comp bio and phys, Part A, physiology. 94:663-665.
Brraullie S, PG, VH y Barden N. 1989. Influence of the central nucleus of the amygdale on the content of corticotropin-releasing factor in the median eminence. Neuroendocrinology. 49: 255- 261.
Bhatnagar S, LT y Vining C. 2005. Prenatal stress differentially affects habituation of corticosterone responses to repeated stress in adult male and female rats. Hormones and behavior. 47(4): 430– 438.
Boyle LM. 2013. A Neuroplasticity hypothesis of chronic stress in the basolateral amygdale. The Yale journal of biology and medicine. 86 (2): 117-125.
Booth DT, BE, MJ, y Lanyon JM. 2004. The influence of incubation temperature on post-hatching fitness characteristics of turtles. Int Congr Ser. 1275: 266– 233.
Chacón D, SJ, CJ y Ash J. 2007. Manual para el manejo y la conservación de las tortugas marinas en Costa Rica; con énfasis en la operación de proyectos en playa y viveros. Sistema Nacional de Áreas de Conservación (SINAC), Ministerio de Ambiente y Energía (MINAE). Gobierno de Costa Rica. San José. 103 pp.
Chrousos GP. 1998. Stressors, stress and neuroendocrine integration of the adaptive response. In: Csermely P (editor). Stress of life: from molecules to man. Ann. N.Y. acad sci. 851: 311– 35.
Dahlof LG, Hard E, Larsson K. 1978. Influence of maternal stress on the development of the fetal genital system. Physiol Behav. 20: 193-195.
Denardo y Lighr P. 1993. Effects of corticosterone on social behavior of male lizard. Hormones and behavior 27: 184 – 199.
Donaldson EM. 1981. The Pituitary-interrenal Axis as an indicator of Stress in fish. En: Stress and fish. Editado por A D Pickering. Academic Press, London, pp. 11-47.
Eckert KL y Eckert SA. 1990. Embryo mortality and hatch success in situ and translocated leatherback sea turtle Dermochelys coriacea eggs. Biological conservation. 53 (1): 37– 46.
Eckert K.L, KAB, FAA y Donnelly M. 1999. Research and management techniques for the conservation of sea turtles (IUCN/SSC marine turtle specialist group publication no. 4). Washington, D.C. (1725 De Sales Street, NW #600, Washington 20036): IUCN/SSC Marine turtle specialist group.
Greenberg N y Wingfield JC. 1987. Stress and reproduction: Reciprocal relationships. P. 389 – 426. In D.O. Norris y Jones R.E (eds). Reproductive endocrinology of fishes, amphibians and reptiles. Wiley, New York.
Greenberg N. 2002. Ethological Aspects of stress in model lizard, Anolis carolinensis. Integ and comp biol. 42: 526–540.
Gregory, LF y Schmid JR. 2001. Stress Responses and Sexing of Wild Kemp’s Ridley Sea Turtles (Lepidochelys kempii) in the Northeastern Gulf of Mexico. General and Comparative Endocrinology, 124(1), 66–74.
Jessop TS y Hamann M. 2005. Interplay between age class, sex and stress response in green turtles (Chelonia mydas). Australian Journal of Zoology, 53(2), 131.
Kapoor A y Matthews SG. 2008. Prenatal stress modifies behavior and hypothalamic-pituitary-adrenal function in fmale guinea pig offspring: Effects of timing of prenatal stress and stage of reproductive cycle. Endocrinology 149 (12); 6406 – 6415.
Kim JJ y Yoon KS. 1998. Stress: metaplastic effects in the hippocampus. Trends in Neurosciences. 21: 505-509.
Koch V, NW, JP, SH, y De la Toba V. 2006. Estimates of sea turtle mortality from poaching and by catch in Bahia Magdalena, Baja California Sur, México. Biol Conserv. 128:327–334
Koshibu K, y Levitt P. 2007. Gene x times Environment Effects: Stress and Memory Dysfunctions Caused by Stress and Gonadal Factor Irregularities during Puberty in Control And TGF-α Hypomorphic Mice. Neuropsychopharmacology, 33(3), 557–565.
Limpus CJ, BV y Miller JD. 1979. Movement induced mortality of loggerhead eggs. Herpetologica. 35: 335 - 338.
Mandyam CD, CEF, EAJ, RCL y Richardson HN. 2008. Stress experienced in utero reduces sexual dichotomies in neurogenesis, microenvironment, and cell death in the adult rat hippocampus. Developmental neurobiology 68 (5); 575 – 589.
Marcovaldi MA y Laurent A. 1996. A six season study of marine turtle nesting at Praia do Forte, Bahia, Brazil, with implications for conservation and management. Chelonian conservation and biology. 2 (1): 55 - 59.
McAllister K. 2000. Cellular and Molecular Mechanims of Dendrite Growth. Cerebral Cortex, 10, 963–973.
McLeod PJ, Brown RE. 1988. The effects of prenatal stress and postweaning housing conditions on parental and sexual behavior of male Long-Evans rats. Psichobioly 16(4): 372-380.
Meisel RL, Dohanich GP, Ward IL. 1979. Effects of prenatal stress on avoindance acquisition, open-field performance and lordotic behavior in male rats.Physiol Behav. 22: 527-530.
Mitra R, JS, MBS, VA y Chattarji S. 2005. Stress duration modulates the spatiotemporal patterns of spine formation in the basolateral amygdala. Proceedings of the national academy of sciences of the United States of America. 102 (26): 9371– 9376.
Morales-Medina JC, Sanchez F, Flores G, Dumont Y, y Quirion R. 2009. Morphological reorganization after repeated corticosterone administration in the hippocampus, nucleus accumbens and amygdala in the rat. Journal of Chemical Neuroanatomy, 38(4), 266–272.
Moorreale SJ, GJ Ruiz, JR Spotila y EA Standora. 1982. Temperature dependent sex determination: current practices, threaten conservation of sea turtles. Science. 216: 1245-1247.
Mrosovsky N y Yntema L. 1980. Temperature dependence of sexual differentiation in sea turtles: Implications for conservation practices. Conservation biology 18: 271-280.
Mrosovsky N. 2008. Against over simplifying the issues on relocating turtle eggs. Environmental management. 41: 465–467.
Mulder EJ, HPG, RA, CHB, RH, VB, JKB, Visser GHA. 2002. Prenatal maternal stress: effects on pregnancy and the unborn child. Early human development. 70: 3-14.
Osadchuk LV. BOB y Bakken M. 2000. Influence of prenatal estress on steroidogenesis in gonads of blue foxes. Russ j of dev biol. 31(3):181-185.
Özdemîr BA y Türkozan O. 2006. Carapacial scute variation in green turtle, Chelonia mydas hatchlings in Northern Cyprus. Turkish journal of zoology. 30 (2): 141-146.
Parmenter CJ. 1980. Incubation of the eggs of the green sea turtle, Chelonia mydas, in Torres Strait, Australia: the effect of movement on hatchability. Aust wild res. 7: 487- 91.
Phillot AD y Parmenter CJ. 2012. Anti-fungal properties of sea turtle cloacal mucus and egg albumen. Marine turtle newsletter. 134: 17 - 21.
Pintus KJ, BJ, GAM y. Broderick NC. 2009. Impact of clutch relocation on green turtle offspring. The journal of wildlife management. 73 (I7): 1151– 1157.
Pottinger TG y Carrick TR. 2000. Indicators of reproductive performance in rainbow trout Oncorhynchus mykiss (Walbaum) selected for high and low responsiveness to stress. Aquaculture research. 31: 367-375.
Reece SE, ACB, BJG y West SA. 2002. The effects of incubation environment, sex and pedigree on the hatchling phenotype in a natural population of loggerhead turtles. Evolutionary ecology research. 4: 737–748.
Rees AF, ET y Margaritoulis D. 2002. Conservation activities for the protection of the loggerhead sea turtle (Caretta caretta) in Kyparissia Bay, during 2001. Testudo. 5: 45-54.
Rodríguez N, Mayer N y Gauna FH. 2007. Effects of prenatal stress on male offspring sexual maturity. Biocell, 31(1): 67-74
Schreck CB, WCS y Fitzpatrick MS. 2001. Effects of stress on fish reproduction gamete quality and progeny. Aquaculture. 197: 3-24.
Stewart MG, DHA, SCK, IVR, VV P, CJ y Popov VI. 2005. Stress suppresses and learning induces plasticity in CA3 of rat hippocampus: A three-dimensional ultrastructural study of thorny excrescences and their postsynaptic densities. Neuroscience. 131(1): 43–54.
Tannahill LA, SWJ, RI, CAF y Fink G. 1991. Corticotrophin-releasing factor-41, vasopressin and oxytocin release into hypophysial portal blood in the rar: Effects of electrical stimulation of the hypothalamus, amygdale and hippocampus. J. Endocrinol. 129: 99-107.
Vyas A1, Mitra R, Shankaranarayana Rao BS, Chattarji S. 2002. Chronic stress induces contrasting patterns of dendritic remodeling in hippocampal and amygdaloid neurons. J Neurosci. 22(15):6810-8.
Wood GE, Young LT, Reagan LP, Chen B y McEwen BS. 2004. Stress-induced structural remodeling in hippocampus: prevention by lithium treatment. Proceedings of the National Academy of Sciences of the United States of America, 101(11), 3973–3978.