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Hepatic chromaffin cells
Perqamon Press
Life Sciences Vol . 15, pp " 267-271 Printed in the U.S .A .
HEPATIC
CHROMAFFIN CELLS
Imelda Martinez*, Radu Racotta and Mâûricio Russek** Escuela National de Ciencias Blol6gicas,
Instituto Politécnico
National, Carpio y Plan de Ayala, México 17, D .F ., Mexico . (Received in final form 17 June 1974)
SUMMARY Chromaffin cells were identified in the liver of mouse, rat, and rabbit . They are found in portal areas, sinusoid walls, or below the connective capsule . The histochemical technique which was used permited to differentiate them from enterochromaffin and mast cells . Liver chromaffin cells could be important for the adrenergic-induced hepatic glucose output . Extra-adrenal chromaffin cells in mammals are relatively few in number in adults and are found mainly in the abdominal paraaortlc area (1) . Catecholamine determination in various organs have frequently showed, besides norepinephrine, the presence of epinephrine . This is usually interpreted as being due to the presence of chromafftn cells in the particular organ (2) . As concerning the liver,
few reports relate to the presence of
epinephrine (3, 4), and the only histochemical evidence .we found in the literature describes dopamine-containing mast cells in ungulates,
localized mainly in thé deep layers of the liver cap-
sule (5) . s wor
represents a part o
the Doctoral Thesis of the author
**The authors are fellows of the "Seccißn de Especiallzacidn Docente e Investigacißn Cientiflca y Tecnolßg ica de la Comisidn de Operacibn y Fomento de Actividades Académlcas del Instituto Politécnico Naclonal" (SEDICT-COFAA) .
267
268
Hepatic Chromaffin Cella
Vol. 15, No . 2
Intra-hepatic epinephrine secretion might represent an important mechanism for an intensified glycogenolysis 1n some physiological instances . As it was shown in a previous work (4), the hepatic concentration of epinephrine decreases markedly shortly after the ingestion of a meal . We undertook an investigation into the presence of chromaffin cells in the liver, whose preliminary results are presented here . MATERIAL AND METHODS Adult mouse,
rat, and rabbit livers were used . Adrenal glands
were used as a positive control for catecholamines and, as a negative control, the intestine (for enterochromaffin cells)~and the liver itself (for mast cells) . The organs were excised under sodium pentobarbital anesthesia . The same fr8gment of the main liver lobule, from the surroundings of the pedicule entrance, was always used . The pieces were immediately fixed in the following mixture (in 1, p .5) : 40% formaldehyde 12 ml ; 5% aqueous potassium dichromate 50 ml ; M-sodium acetate 20 ml, and distilled water to 100 ml . The pieces were kept for 48 hours in the fixative, then washed with distilled water for 1 1/2 - 2 hr . Sections of 10 ~ were prepared using a freezing microtome . Sevki's histochemical technique (in 6) was used, with some of Coupland's modifications (in 1, p .13) . The sections were kept in Giemsa solution during 48 hours, washed 30 minutes with distilled watér, differentiated in 0 .2% acetic acid solution, dehydrated through 96~alcohol to absolute alcohol and taken through xylene before mounting under cover glasses with Canada balsame . RESULTS AND DISCUSSION The technique described readily allows epinephrine-containing cells (yellow-green) to be differentiated from noreplnephrine-
Vol. 15, No . 2
Hepatic Chrooalfin Cells
269
containing cells (blue-green) and from enterochramaffin (orange) and mast cells (red-purple) in controlled sections of gut and adrenal gland . On the basis of these staining reactions we were able to identify enterochromaffin cells in the gut and many isolated mast cells, but also chramaffin calls, in the sections of liver . The cells identified as chromaffin cells In the liver had a similar color reaction to those in controlled sections of the adrenal medulla and they are to be found usually forming clusters in the portal areas and also as single cells In the walls of liver sinusoids and in the region Immediately below the connective capsule (Figure 1) . The identification of chromaffin cells inside the liver parenchyma offers, at last, a firm support for a physiological action of epinephrine on hepatic glycogenolysis . This action seemed to be no more than a pharmacological curiosity since systemic concentration of the hormone never reaches a level which would elicit such an effect (7, 8) . Minute quantities of epinephrine secreted from the described chromaffin cells in the Immediate vicinity of hepatic cells could attain the necessary concentration to produce glycogenolysis without modifying the systemic level of the hormone.
270
Hepatic Chromaffin Cells
Vol . 15, No . 2
FIG . 1 Photomicrographs of liver sections : A, mouse ; B, rat ; C, rabbit . Chromaffin cell clusters (c) are located in portal areas (p) or below the hepatic capsule (hc) ; h, hepatocytes ; m, mast cells . X 800.
Vol. 15, No . 2
Hepatic Chromaffin Cells
271
REFERENCES 1 . R . E . COUPLAND~:The Natural Hintor Longmans, Green ~ Co . t , on on
of Chromaffin Cells,
2 . U . S . VON EULER, Science 173 202-206 (1971) . 3 . T . S . HARRISON, and J . F . SEATON, Am . J . Physiol . 210 599-600 (1966) . 4 . R . RACOTTA, C . VEGA, and M. RUSSEK, Fed Proc . 31 309 Abs . (1972) . 5 . R . E . COUPLAND, and I . D . HEATH, J . Endocrinol . 22 71-76 (1961) 6 . A . G . E . PEARSE, Hist Madrid, p . 535-53
uimica Tebrica
A licada, Aguilar S .A .,
7 . Z . EZDINLI, and J . E . SOKAL, Endocrinology 78 47-54 (1966) . 8. J . E . SOKAL, E . J. SARCIONE, and A . M . HENDERSON, Endocrinology 74 930-938 (1964) .
Life Sciences Vol . 15, pp " 267-271 Printed in the U.S .A .
HEPATIC
CHROMAFFIN CELLS
Imelda Martinez*, Radu Racotta and Mâûricio Russek** Escuela National de Ciencias Blol6gicas,
Instituto Politécnico
National, Carpio y Plan de Ayala, México 17, D .F ., Mexico . (Received in final form 17 June 1974)
SUMMARY Chromaffin cells were identified in the liver of mouse, rat, and rabbit . They are found in portal areas, sinusoid walls, or below the connective capsule . The histochemical technique which was used permited to differentiate them from enterochromaffin and mast cells . Liver chromaffin cells could be important for the adrenergic-induced hepatic glucose output . Extra-adrenal chromaffin cells in mammals are relatively few in number in adults and are found mainly in the abdominal paraaortlc area (1) . Catecholamine determination in various organs have frequently showed, besides norepinephrine, the presence of epinephrine . This is usually interpreted as being due to the presence of chromafftn cells in the particular organ (2) . As concerning the liver,
few reports relate to the presence of
epinephrine (3, 4), and the only histochemical evidence .we found in the literature describes dopamine-containing mast cells in ungulates,
localized mainly in thé deep layers of the liver cap-
sule (5) . s wor
represents a part o
the Doctoral Thesis of the author
**The authors are fellows of the "Seccißn de Especiallzacidn Docente e Investigacißn Cientiflca y Tecnolßg ica de la Comisidn de Operacibn y Fomento de Actividades Académlcas del Instituto Politécnico Naclonal" (SEDICT-COFAA) .
267
268
Hepatic Chromaffin Cella
Vol. 15, No . 2
Intra-hepatic epinephrine secretion might represent an important mechanism for an intensified glycogenolysis 1n some physiological instances . As it was shown in a previous work (4), the hepatic concentration of epinephrine decreases markedly shortly after the ingestion of a meal . We undertook an investigation into the presence of chromaffin cells in the liver, whose preliminary results are presented here . MATERIAL AND METHODS Adult mouse,
rat, and rabbit livers were used . Adrenal glands
were used as a positive control for catecholamines and, as a negative control, the intestine (for enterochromaffin cells)~and the liver itself (for mast cells) . The organs were excised under sodium pentobarbital anesthesia . The same fr8gment of the main liver lobule, from the surroundings of the pedicule entrance, was always used . The pieces were immediately fixed in the following mixture (in 1, p .5) : 40% formaldehyde 12 ml ; 5% aqueous potassium dichromate 50 ml ; M-sodium acetate 20 ml, and distilled water to 100 ml . The pieces were kept for 48 hours in the fixative, then washed with distilled water for 1 1/2 - 2 hr . Sections of 10 ~ were prepared using a freezing microtome . Sevki's histochemical technique (in 6) was used, with some of Coupland's modifications (in 1, p .13) . The sections were kept in Giemsa solution during 48 hours, washed 30 minutes with distilled watér, differentiated in 0 .2% acetic acid solution, dehydrated through 96~alcohol to absolute alcohol and taken through xylene before mounting under cover glasses with Canada balsame . RESULTS AND DISCUSSION The technique described readily allows epinephrine-containing cells (yellow-green) to be differentiated from noreplnephrine-
Vol. 15, No . 2
Hepatic Chrooalfin Cells
269
containing cells (blue-green) and from enterochramaffin (orange) and mast cells (red-purple) in controlled sections of gut and adrenal gland . On the basis of these staining reactions we were able to identify enterochromaffin cells in the gut and many isolated mast cells, but also chramaffin calls, in the sections of liver . The cells identified as chromaffin cells In the liver had a similar color reaction to those in controlled sections of the adrenal medulla and they are to be found usually forming clusters in the portal areas and also as single cells In the walls of liver sinusoids and in the region Immediately below the connective capsule (Figure 1) . The identification of chromaffin cells inside the liver parenchyma offers, at last, a firm support for a physiological action of epinephrine on hepatic glycogenolysis . This action seemed to be no more than a pharmacological curiosity since systemic concentration of the hormone never reaches a level which would elicit such an effect (7, 8) . Minute quantities of epinephrine secreted from the described chromaffin cells in the Immediate vicinity of hepatic cells could attain the necessary concentration to produce glycogenolysis without modifying the systemic level of the hormone.
270
Hepatic Chromaffin Cells
Vol . 15, No . 2
FIG . 1 Photomicrographs of liver sections : A, mouse ; B, rat ; C, rabbit . Chromaffin cell clusters (c) are located in portal areas (p) or below the hepatic capsule (hc) ; h, hepatocytes ; m, mast cells . X 800.
Vol. 15, No . 2
Hepatic Chromaffin Cells
271
REFERENCES 1 . R . E . COUPLAND~:The Natural Hintor Longmans, Green ~ Co . t , on on
of Chromaffin Cells,
2 . U . S . VON EULER, Science 173 202-206 (1971) . 3 . T . S . HARRISON, and J . F . SEATON, Am . J . Physiol . 210 599-600 (1966) . 4 . R . RACOTTA, C . VEGA, and M. RUSSEK, Fed Proc . 31 309 Abs . (1972) . 5 . R . E . COUPLAND, and I . D . HEATH, J . Endocrinol . 22 71-76 (1961) 6 . A . G . E . PEARSE, Hist Madrid, p . 535-53
uimica Tebrica
A licada, Aguilar S .A .,
7 . Z . EZDINLI, and J . E . SOKAL, Endocrinology 78 47-54 (1966) . 8. J . E . SOKAL, E . J. SARCIONE, and A . M . HENDERSON, Endocrinology 74 930-938 (1964) .