TY  - JOUR
A1  - Vonhof, S.
A1  - Sirén, Anna-Leena
A1  - Feuerstein, Giora
T1  - Volume-dependent spatial distribution of microinjected thyrotropin-releasing hormone (TRH) into the medial preoptic nucleus of the rat
N2  - The present study was performed to qua ntify the distribution of a peptide neurotransmitter after microinjection into the medial preoptic area (POM), using a technique suitable for conscious animal preparations. The results indicate that only 50-ni volumes of injected tracer were sufficiently localized with 77 ± 9% recovery in the POM. Injections of higher volumes resulted in an increasing spread of tracer into distant anatomical regions and structures, including the needle tract and cerebral ventricles. The amount of tracer localized in the POM decreased to 38±4% (200 nl) (P < 0.05) and 41 ±8% (500 nl) (P <0.05), respectively. The data suggest that the volume of injection is critical for intraparenchymal injections into structures of a diameter of I mm or less, such as the POM and should not exceed 50 nl in conscious animal preparations.
KW  - Neurophysiologie
KW  - Neurobiologie
KW  - Autoradiography
KW  - Microinjection
KW  - Hypothalamus
KW  - TRH
KW  - Neuropeptides
KW  - [3H][3Me-His2]-TRH
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47421
ER  - 
TY  - JOUR
A1  - Paakkari, I.
A1  - Sirén, Anna-Leena
A1  - Nurminen, M.-L.
A1  - Svartström-Fraser, M.
T1  - Injection of thyrotropin releasing hormone into the locus coeruleus increases blood pressure
N2  - Thyrotropin releasing hormone (TRH), 10 pmol kg-1 injected in the region of locus coeruleus, caused a rapid (within 1 min) rise of mean arterial pressure in the urethane- naesthetized rat. No clear-cut effects in heart rate or ventilation were observed. When TRH was injected into the lateral ventricle, a dose more than 10-fold higher was required to achieve a comparable rise in arterial pressure. It is concluded that TRH may have a physiological rote in centrat cardiovascular regulation.
KW  - Thyreotropin-Releasinghormon
KW  - Blutdruck
KW  - Locus coeruleus
KW  - TRH
KW  - blood pressure
KW  - locus coeruleus
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72894
ER  - 
TY  - JOUR
A1  - Paakkari, I.
A1  - Nurminen, M-L.
A1  - Sirén, Anna-Leena
T1  - Cardioventilatory effects of TRH in anesthetized rats: role of the brainstem
N2  - Cardioventilator responses were studied in anaesthetized rats after injections of TRH into either the lateral (i.c.v. lat) or the fourth (i.c.v. IV) cerebral ventricles. TRH induced a morerapid hypertensive effect i.c.v. IV than i.c.v. lat. Blocking of the cerebral aqueduct abolished the hypertensive and tachypnoeic effects of TRH i.c.v. lat but not those of TRH i.c.v. IV. It is concluded that TRH increased blood pressure and ventilation rate via brain stem structures close to the fourtli ventricle.
KW  - Neurobiologie
KW  - TRH
KW  - Cardiovascular
KW  - Ventilation
KW  - Brain stem
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63277
ER  -