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. 1990 Apr;423:111–135. doi: 10.1113/jphysiol.1990.sp018014

An intracellular study of grafted and in situ preoptic area neurones in brain slices from normal and hypogonadal mice.

J P Hodgkiss 1, J S Kelly 1
PMCID: PMC1189749  PMID: 2388147

Abstract

1. Intracellular recordings have been obtained from forty-one preoptic area (POA) neurones at times up to 14 months after they were grafted into the third ventricle of the mouse. Thirty-one neurones were in grafts from hypogonadal (hpg) mice in which a reversal of the hypogonadism was seen (responders), six were in grafts from hpg mice in which no such reversal occurred (non-responders) and four were in grafts from normal mice. 2. The grafted neurones had a mean resting potential (Em) of -57 mV, a mean apparent input resistance (Rm) of 136 M omega and a mean membrane time constant (tau m) of 7.7 ms. The slopes of the current-voltage (I-V) relations were linear. Approximately a quarter of neurones in responders fired action potentials spontaneously either singly or in bursts. Such activity could underlie the release of gonadotrophin hormone-releasing hormone (GnRH) which is known to occur from such grafts. 3. Two types of response were seen when these neurones were depolarized to firing threshold from Em, in one group a single action potential was discharged; in the other group one or more action potentials arising from a transient, slowly rising and falling depolarization (low-threshold response, LTR) was recorded. Some cells in the former category exhibited a LTR when depolarized from a potential more negative than Em. 4. The commonest response to stimulation of the median eminence in responders was an EPSP either alone or in combination with an IPSP. Antidromic action potentials were seen in four neurones and in two of these cells excitatory synaptic inputs could be demonstrated when the host hypothalamus adjacent to the graft was stimulated. It is suggested that these responses may represent activation of an afferent input from the host to neurones in the graft. 5. The morphology of neurones in POA grafts was determined by intrasomatic injection of horseradish peroxidase (HRP). A variety of profiles were seen and although some neurones extended over distances of up to 635 microns and branched extensively only one appeared to enter the host tissue at the ventrolateral edge of the graft. 6. A comparison was made between grafted POA neurones and cells in the medial preoptic area (MPOA), a region which constituted a significant component of the grafted tissue. No significant difference was noted between neurones in the graft and neurones in the MPOA in terms of their passive membrane properties. With regard to the active properties MPOA neurones could also be classified according to whether or not a LTR was elicited when the neurone was depolarized from Em. The major difference between the grafted neurones and those in the MPOA lay in the proportion of cells which exhibited a LTR under such conditions, being significantly greater in the latter group.

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Selected References

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  1. Anderson P., Storm J., Wheal H. V. Thresholds of action potentials evoked by synapses on the dendrites of pyramidal cells in the rat hippocampus in vitro. J Physiol. 1987 Feb;383:509–526. doi: 10.1113/jphysiol.1987.sp016425. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bicknell R. J., Leng G. Relative efficiency of neural firing patterns for vasopressin release in vitro. Neuroendocrinology. 1981 Nov;33(5):295–299. doi: 10.1159/000123248. [DOI] [PubMed] [Google Scholar]
  3. Björklund A., Dunnett S. B., Stenevi U., Lewis M. E., Iversen S. D. Reinnervation of the denervated striatum by substantia nigra transplants: functional consequences as revealed by pharmacological and sensorimotor testing. Brain Res. 1980 Oct 20;199(2):307–333. doi: 10.1016/0006-8993(80)90692-7. [DOI] [PubMed] [Google Scholar]
  4. Björklund A., Gage F. H. Grafts of fetal septal cholinergic neurons to the hippocampal formation in aged or fimbria-fornix-lesioned rats. Ann N Y Acad Sci. 1987;495:120–137. doi: 10.1111/j.1749-6632.1987.tb23671.x. [DOI] [PubMed] [Google Scholar]
  5. Björklund A., Schmidt R. H., Stenevi U. Functional reinnervation of the neostriatum in the adult rat by use of intraparenchymal grafting of dissociated cell suspensions from the substantia nigra. Cell Tissue Res. 1980;212(1):39–45. doi: 10.1007/BF00234031. [DOI] [PubMed] [Google Scholar]
  6. Björklund A., Stenevi U. Intracerebral neural implants: neuronal replacement and reconstruction of damaged circuitries. Annu Rev Neurosci. 1984;7:279–308. doi: 10.1146/annurev.ne.07.030184.001431. [DOI] [PubMed] [Google Scholar]
  7. Charlton H. M., Barclay A. N., Williams A. F. Detection of neuronal tissue from brain grafts with anti-Thy-1.1 antibody. 1983 Oct 27-Nov 2Nature. 305(5937):825–827. doi: 10.1038/305825a0. [DOI] [PubMed] [Google Scholar]
  8. Charlton H. M., Jones A. J., Whitworth D., Gibson M. J., Kokoris G., Zimmerman E. A., Silverman A. J. The effects of the age of intracerebroventricular grafts of normal preoptic area tissue upon pituitary and gonadal function in hypogonadal (HPG) mice. Neuroscience. 1987 Apr;21(1):175–181. doi: 10.1016/0306-4522(87)90331-9. [DOI] [PubMed] [Google Scholar]
  9. Charlton H. M. Neural transplants and the repair of neuroendocrine and reproductive deficiencies. Oxf Rev Reprod Biol. 1987;9:379–397. [PubMed] [Google Scholar]
  10. Connor J. A., Stevens C. F. Voltage clamp studies of a transient outward membrane current in gastropod neural somata. J Physiol. 1971 Feb;213(1):21–30. doi: 10.1113/jphysiol.1971.sp009365. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dingledine R., Dodd J., Kelly J. S. The in vitro brain slice as a useful neurophysiological preparation for intracellular recording. J Neurosci Methods. 1980 Aug;2(4):323–362. doi: 10.1016/0165-0270(80)90002-3. [DOI] [PubMed] [Google Scholar]
  12. Dunnett S. B., Björklund A., Stenevi U., Iversen S. D. Behavioural recovery following transplantation of substantia nigra in rats subjected to 6-OHDA lesions of the nigrostriatal pathway. I. Unilateral lesions. Brain Res. 1981 Jun 29;215(1-2):147–161. doi: 10.1016/0006-8993(81)90498-4. [DOI] [PubMed] [Google Scholar]
  13. Dutton A., Dyball R. E. Phasic firing enhances vasopressin release from the rat neurohypophysis. J Physiol. 1979 May;290(2):433–440. doi: 10.1113/jphysiol.1979.sp012781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gardette R., Alvarado-Mallart R. M., Crepel F., Sotelo C. Electrophysiological demonstration of a synaptic integration of transplanted Purkinje cells into the cerebellum of the adult Purkinje cell degeneration mutant mouse. Neuroscience. 1988 Mar;24(3):777–789. doi: 10.1016/0306-4522(88)90066-8. [DOI] [PubMed] [Google Scholar]
  15. Gibson M. J., Charlton H. M., Perlow M. J., Zimmerman E. A., Davies T. F., Krieger D. T. Preoptic area brain grafts in hypogonadal (hpg) female mice abolish effects of congenital hypothalamic gonadotropin-releasing hormone (GnRH) deficiency. Endocrinology. 1984 May;114(5):1938–1940. doi: 10.1210/endo-114-5-1938. [DOI] [PubMed] [Google Scholar]
  16. Gibson M. J., Kokoris G. J., Silverman A. J. Positive feedback in hypogonadal female mice with preoptic area brain transplants. Neuroendocrinology. 1988 Aug;48(2):112–119. doi: 10.1159/000124998. [DOI] [PubMed] [Google Scholar]
  17. Gibson M. J., Krieger D. T., Charlton H. M., Zimmerman E. A., Silverman A. J., Perlow M. J. Mating and pregnancy can occur in genetically hypogonadal mice with preoptic area brain grafts. Science. 1984 Aug 31;225(4665):949–951. doi: 10.1126/science.6382608. [DOI] [PubMed] [Google Scholar]
  18. Gibson M. J., Moscovitz H. C., Kokoris G. J., Silverman A. J. Plasma LH rises rapidly following mating in hypogonadal female mice with preoptic area (POA) brain grafts. Brain Res. 1987 Oct 20;424(1):133–138. doi: 10.1016/0006-8993(87)91202-9. [DOI] [PubMed] [Google Scholar]
  19. Gibson M. J., Silverman A. J., Kokoris G. J., Zimmerman E. A., Perlow M. J., Charlton H. M. GnRH cell brain grafts. Correction of hypogonadism in mutant mice. Ann N Y Acad Sci. 1987;495:296–305. doi: 10.1111/j.1749-6632.1987.tb23682.x. [DOI] [PubMed] [Google Scholar]
  20. Grace A. A., Llinás R. Morphological artifacts induced in intracellularly stained neurons by dehydration: circumvention using rapid dimethyl sulfoxide clearing. Neuroscience. 1985 Oct;16(2):461–475. doi: 10.1016/0306-4522(85)90018-1. [DOI] [PubMed] [Google Scholar]
  21. Haas H. L., Schaerer B., Vosmansky M. A simple perfusion chamber for the study of nervous tissue slices in vitro. J Neurosci Methods. 1979 Dec;1(4):323–325. doi: 10.1016/0165-0270(79)90021-9. [DOI] [PubMed] [Google Scholar]
  22. Hounsgaard J., Yarom Y. Intrinsic control of electroresponsive properties of transplanted mammalian brain neurons. Brain Res. 1985 Jun 3;335(2):372–376. doi: 10.1016/0006-8993(85)90497-4. [DOI] [PubMed] [Google Scholar]
  23. Jahnsen H., Llinás R. Electrophysiological properties of guinea-pig thalamic neurones: an in vitro study. J Physiol. 1984 Apr;349:205–226. doi: 10.1113/jphysiol.1984.sp015153. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Kokoris G. J., Lam N. Y., Ferin M., Silverman A. J., Gibson M. J. Transplanted gonadotropin-releasing hormone neurons promote pulsatile luteinizing hormone secretion in congenitally hypogonadal (hpg) male mice. Neuroendocrinology. 1988 Jul;48(1):45–52. doi: 10.1159/000124988. [DOI] [PubMed] [Google Scholar]
  25. Krieger D. T., Perlow M. J., Gibson M. J., Davies T. F., Zimmerman E. A., Ferin M., Charlton H. M. Brain grafts reverse hypogonadism of gonadotropin releasing hormone deficiency. Nature. 1982 Jul 29;298(5873):468–471. doi: 10.1038/298468a0. [DOI] [PubMed] [Google Scholar]
  26. Lamb T. D. An inexpensive digital tape recorder suitable for neurophysiological signals. J Neurosci Methods. 1985 Oct;15(1):1–13. doi: 10.1016/0165-0270(85)90057-3. [DOI] [PubMed] [Google Scholar]
  27. Low W. C., Lewis P. R., Bunch S. T., Dunnett S. B., Thomas S. R., Iversen S. D., Björklund A., Stenevi U. Function recovery following neural transplantation of embryonic septal nuclei in adult rats with septohippocampal lesions. Nature. 1982 Nov 18;300(5889):260–262. doi: 10.1038/300260a0. [DOI] [PubMed] [Google Scholar]
  28. Minami T., Oomura Y., Sugimori M. Electrophysiological properties and glucose responsiveness of guinea-pig ventromedial hypothalamic neurones in vitro. J Physiol. 1986 Nov;380:127–143. doi: 10.1113/jphysiol.1986.sp016276. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Perlow M. J., Kokoris G., Gibson M. J., Silverman A. J., Kreiger D. T., Zimmerman E. A. Accessory olfactory bulb transplants correct hypogonadism in mutant mice. Brain Res. 1987 Jul 7;415(1):158–162. doi: 10.1016/0006-8993(87)90280-0. [DOI] [PubMed] [Google Scholar]
  30. Randle J. C., Renaud L. P. Actions of gamma-aminobutyric acid on rat supraoptic nucleus neurosecretory neurones in vitro. J Physiol. 1987 Jun;387:629–647. doi: 10.1113/jphysiol.1987.sp016592. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Rutherford A., Garcia-Munoz M., Dunnett S. B., Arbuthnott G. W. Electrophysiological demonstration of host cortical inputs to striatal grafts. Neurosci Lett. 1987 Dec 29;83(3):275–281. doi: 10.1016/0304-3940(87)90099-1. [DOI] [PubMed] [Google Scholar]
  32. Schiess M. C., Joëls M., Shinnick-Gallagher P. Estrogen priming affects active membrane properties of medial amygdala neurons. Brain Res. 1988 Feb 9;440(2):380–385. doi: 10.1016/0006-8993(88)91012-8. [DOI] [PubMed] [Google Scholar]
  33. Segal M., Azmitia E. C. Fetal raphe neurons grafted into the hippocampus develop normal adult physiological properties. Brain Res. 1986 Jan 29;364(1):162–166. doi: 10.1016/0006-8993(86)90997-2. [DOI] [PubMed] [Google Scholar]
  34. Segal M., Bjorklund A., Gage F. H. Transplanted septal neurons make viable cholinergic synapses with a host hippocampus. Brain Res. 1985 Jun 17;336(2):302–307. doi: 10.1016/0006-8993(85)90656-0. [DOI] [PubMed] [Google Scholar]
  35. Silverman A. J., Kokoris G. J., Gibson M. J. Quantitative analysis of synaptic input to gonadotropin-releasing hormone neurons in normal mice and hpg mice with preoptic area grafts. Brain Res. 1988 Mar 8;443(1-2):367–372. doi: 10.1016/0006-8993(88)91635-6. [DOI] [PubMed] [Google Scholar]
  36. Silverman A. J., Zimmerman E. A., Gibson M. J., Perlow M. J., Charlton H. M., Kokoris G. J., Krieger D. T. Implantation of normal fetal preoptic area into hypogonadal mutant mice: temporal relationships of the growth of gonadotropin-releasing hormone neurons and the development of the pituitary/testicular axis. Neuroscience. 1985 Sep;16(1):69–84. doi: 10.1016/0306-4522(85)90048-x. [DOI] [PubMed] [Google Scholar]
  37. Sotelo C., Alvarado-Mallart R. M. Embryonic and adult neurons interact to allow Purkinje cell replacement in mutant cerebellum. Nature. 1987 Jun 4;327(6121):421–423. doi: 10.1038/327421a0. [DOI] [PubMed] [Google Scholar]
  38. Sotelo C., Alvarado-Mallart R. M. Reconstruction of the defective cerebellar circuitry in adult Purkinje cell degeneration mutant mice by Purkinje cell replacement through transplantation of solid embryonic implants. Neuroscience. 1987 Jan;20(1):1–22. doi: 10.1016/0306-4522(87)90002-9. [DOI] [PubMed] [Google Scholar]
  39. Young L. S., Detta A., Clayton R. N., Jones A., Charlton H. M. Pituitary and gonadal function in hypogonadotrophic hypogonadal (hpg) mice bearing hypothalamic implants. J Reprod Fertil. 1985 May;74(1):247–255. doi: 10.1530/jrf.0.0740247. [DOI] [PubMed] [Google Scholar]

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