PubMed Health⌕ Search

Biomedical subjects

G Krauthamer

Publications and source records attributed to G Krauthamer.

9 recordsLinked to original sources
PubMed1996

Early history of IBRO: the birth of organized neuroscience.

To celebrate the thirtieth anniversary of the founding of the International Brain Research Organization (IBRO), a symposium was organized for the III Congress of the World Federation of Neuroscientists in Montreal to present, on 7 August 1991, the recollections of some of the early participants in IBRO's history and to place it in the context of other significant world organizations. Edited and slightly condensed transcripts of the talks together with the discussions are presented. L. Marshall reviewed the antecedent conferences that led to the Moscow Colloquium in 1958 and the subsequent formation of IBRO with UNESCO support. The ambience of that period for scientific organization on an international level was discussed by W. A. Rosenblith who emphasized how IBRO goals fitted into the rising interest in brain and behavior research. The scientific careers of six past executive secretaries were briefly reviewed by P. Gloor, with special tribute to the first, Herbert Jasper. One of IBRO's major achievements, the world survey of resources and needs in brain research, was described first-hand by G. Krauthamer. To discuss IBRO's image, C. Blakemore invoked the travails of reorganization and recovery from a period of inactivity. Finally, placing IBRO in a national and international context, S. Cozzens presented the perspective of the historian of sociology on an upbeat note.

History, 20th Century↗
PubMed1984

Organization of the intercollicular pathway in rat.

The intercollicular pathway of the rat was studied using autoradiographic (ARG) and horseradish peroxidase (HRP) tracing techniques. The HRP experiments demonstrated that the cells of origin of the intertectal pathway were located primarily in the rostral stratum griseum intermediale ( SGI ), stratum album intermedium (SAI) and stratum griseum profundum (SGP). Intertectal neurons were in most cases multipolar and had average somal diameters which ranged between 8 and 33 micron. Only a small number of superficial layer neurons contributed axons to the intercollicular pathway. ARG tracing showed that the intertectal pathway terminated in the deep layers of the rostral one half of the colliculus. The primary terminal zone was SGP. In addition, labeled axons left this region and coursed dorsally to terminate in a series of patches in the lower SGI and upper SAI. A small number of labeled fibers also reached the stratum opticum (SO) and lower stratum griseum superficiale (SGS).

Animals↗
PubMed1976

Synchronization of the electrocorticogram by visceral and somatic bradykinin stimulation in anesthetized cats.

The cortical response to visceral and somatic bradykinin stimulation was studied in cats under light to moderate pentobarbital anesthesia. Following the injection of bradykinin into arteries supplying visceral organs and somatic structures, a marked cortical synchronization was recorded. The bilateral, rhythmic discharge in the theta to alpha range was best seen on SI; occasionally the contralateral SI response was more prominent. The cortical synchronization and its distribution were the same for visceral and somatic stimulation. There was only minimal response desensitization to multiple injections of bradykinin in rapid succession. Following transection of the thoracolumbar spinal cord, synchronization failed to develop after hindlimb injections but continued to be seen after forelimb stimulation; similarly, partial denervation of a limb blocked the bradykinin response. No synchronization or desynchronization could be produced by epinephrine and nitroglycerine which caused phasic changes in systemic blood pressure equal to or greater than those seen with bradykinin. The results are discussed in terms of possible pathways and receptors. It is suggested that bradykinin acts primarily on free nerve endings common to visceral and deep somatic tissue with convergence of impulses occurring at spinal and higher levels. The preferential response of SI may reflect afferent activity generated by natural, painful stimulation of deep somatic and visceral organs. Normally, this component would be masked by the concomitant non-specific arousal response of the medial reticulo-thalamic system which was depressed by the anesthetic.

Afferent Pathways↗
PubMed1969

Central nervous system activity associated with the pain evoked by bradykinin and its alteration by morphine and aspirin.

Synthetic bradykinin, a nonapeptide formed from alpha-2 globulin in plasma, injected intra-arterially or intraperitoneally in cats in doses of 10-50 mug, evoked activity in the central nervous system in pathways associated with the signaling of pain. Similar injections of bradykinin in intact normal cats and dogs evoked manifestations of pain, and in conscious humans elicited verbal reports of pain perceived in the area of injection. Single unit activity was recorded in the medial reticular formation of the brainstem, in the medial thalamus and, more laterally, among the posterior group nuclei and the suprageniculate nucleus. Bradykinin did not evoke any cortical or subcortical slow potentials such as those evoked by electrical stimulation of the foot pads. When bradykinin was given together with the electrical stimulus, the responses evoked by the latter were blocked. Morphines uppressed bradykinin-evoked activity. Aspirin caused marked fluctuations in activity, unrelated to the bradykinin injection; the bradykinin block of evoked potentials could no longer be observed after aspirin dosage. The results are discussed in terms of the peripheral and central sites of analgesic action and the likelihood of the existence of chemosensitive pain receptors.

Animals↗
PubMedDate not supplied

Unit responses in the ventrobasal thalamus (VPL) of the cat of bradykinin injected into somatic and visceral arteries.

Under light to moderate sodium pentobarbital anesthesia one half of the thalamic neurons displaying place and modality specific responses to low intensity mechanical stimulation of contralateral receptive fields also responded, by excitation or by inhibition, to bradykinin injections into somatic and visceral arteries. Partial or complete somatovisceral convergence was commonly seen in neurons with otherwise typical lemniscal properties. The response intensities varied considerably for different neurons; the responses to somatic bradykinin were always stronger than to visceral injections. The time course of the response was comparable to that seen in peripheral nerves, other central sites, and the behavioral reaction to bradykinin. Control experiments indicated the independence of the bradykinin responses from variations in blood pressure or general arousal effects. It is suggested that modulation of ventrobasal thalamic activity may be an important factor in central nociceptive processing.

Animals↗