Interstitial cells

Erythropoietin is a growth factor produced by interstitial cells of the kidney in response to hypoxia. Erythropoietin stimulates haematopoiesis in the bone marrow. Recombinant human erythropoietin is used to treat anemias, e.g. anemia caused by chronic renal failure and anemia in AIDS and cancer patients. 

Three rats had interstitial cell ademona of testis, 1 renal nephroblastoma, 1 rhabdomyosarcoma. 

F (lipidosis in ovarian interstitial cells of 8/8, ovarian interstitial cell hypertrophy)... 

F (decreased fertility vacuolar cytoplasmic alteration of ovarian interstitial cells increased follicular and luteal activity)... 

Rat 13wk (Fischer- 344) 7 d/wk (F) 220 M 430 M (significantly decreased absolute and relative testis weight and small testes atrophy of the seminiferous tubules) 65 F (hypertrophy inflammation of ovarian interstitial cells) NTP 1994 TCP... 

In a 2-year feeding study in rats, ovarian interstitial cell hyperplasia was observed in rats exposed to 15 mg/kg/day tricresyl phosphate, but no effect was seen at 7 mg/kg/day (NTP 1994). No effects on male reproductive tissues were seen at < 13 mg/kg/day. No effects on reproductive tissues in either sex were observed in 2-year feeding studies in mice (27 mg/kg/day in males, 37 mg/kg/day in females). 

Tricresyl phosphate (a complex mixture containing tri-o, Xn-m-, and tri-para-cresyl phosphate that is used in certain hydraulic fluids) and TOCP are demonstrated testicular toxicants in rodents (Carlton et al. 1987 Somkuti et al. 1987a, 1987b). Tricresyl phosphate also has been shown to impair in vivo fertility in rats and mice (Carlton et al. 1987 Chapin et al. 1988a). In addition, tricresyl phosphate-treated female rats displayed vacuolar cytoplasmic alteration of ovarian interstitial cells (Carlton et al. 1987 NTP 1994). Reproductive effects have also been seen after oral exposure to butylated triphenyl phosphate (Latendresse et al. 1994b). 

A mixed isomer preparation of TCP (containing <0.1% tri-ort/zo-cresyl phosphate) produced histological changes in reproductive organs in both sexes of rats and female mice in 13-week and 2-year bioassays (NTP 1994). Ovarian interstitial cell hypertrophy occurred in female mice and female rats exposed to gavage doses of 50-800 mg/kg/day for 13 weeks, in female rats exposed to dietary doses of 65 and 120 ng/kg/day for 13 weeks, and in female rats exposed to dietary doses of 9 or 18 mg/kg/day for 2 years (NTP 1994). Atrophy of the seminiferous tubules occurred in male rats that received gavage doses of 400 and 800 mg/kg/day for 13 weeks and in male rats exposed to dietary doses of 470 and 940 mg/kg/day for 13 weeks (NTP 1994). 

Setola, V., Hufeisen, S.J., Grande-Alien, K.J., Vesely, I., Glennon, R.A., Blough, B., Rothman, R.B., and Roth, B.L., 3,4-Methylenedioxymethamphetamine (MDMA, Ecstasy ) induces fenfluraminelike proliferative actions on human cardiac valvular interstitial cells in vitro, Mol. Pharmacol. 63(6), 1223-1229, 2003. 

The involvement of mast cells in host protection against nematode infection is well characterized in T. spiralis infection. W/Wv mice exhibited a significant delay in worm expulsion, and treatment with either anti-SCF or anti-SCF receptor monoclonal antibody dramatically inhibited mast cell responses and expulsion of T. spiralis for the duration of treatment (Donaldson et al., 1996). W/Wv mice also lack interstitial cells of cajal and intraepithelial y T cells (Maeda et al., 1992 Puddington et al., 1994), which may contribute to the impaired response in these animals (see below). However, supporting evidence of a role for mast cells in protection against T. spiralis comes from studies in which overexpression of IL-9 in mice (which is known to influence the mast cell responses see above) resulted in an extremely rapid mast cell-dependent expulsion of T. spiralis (Faulkner et al., 1997). 

Enteric Neuropathies. Different kinds of familial visceral neuropathies have been described the dominant type 1 [134], the recessive type 2 [135] and a recessive form with calcified basal ganglia [134], Furthermore, aganglionosis of the small bowel (Hirschsprung s disease) [136], hypergan-glionosis (neurofibromatosis) [137], neuronal intestinal dysplasia [138] and Parkinson s disease [139] are neuropathies to consider. The recognition of the pacemaker cells of the small bowel, the interstitial cells of Cajal, has prompted studies to detect abnormalities of these cells, another possible cause of pseudoobstruction [140],... 

Kenny SE, Vanderwinden JM, Rintala RJ, Connell MG, Lloyd DA, Vanderhaegen JJ, et al Delayed maturation of the interstitial cells of Cajal A new diagnosis for transient neonatal pseudoobstruction. Report of two cases. J Pediatr Surg 1998 33 94-98. 

EPO in the human adult is synthesized almost exclusively by specialized kidney cells (peritubular interstitial cells of the kidney cortex and upper medulla). Minor quantities are also synthesized in the liver, which represents the primary EPO-producing organ of the foetus. 

Laboratory studies with mice and rats have conclusively demonstrated that the injection of cadmium metal or salts causes malignancies (sarcoma) at the site of injection and testicular tumors. However, the simultaneous administration of zinc is protective against sarcoma and interstitial cell tumor development (USEPA 1980). In rats, no dose-related increases in tumors were found at maximum oral daily doses of 4.4 mg Cd/kg BW (USPHS 1993). Among humans, the available epidemiological evidence is not sufficient to conclude that cadmium is definitely implicated as a carcinogen (USEPA 1980 Nomiyama 1982), although cadmium exposure is associated with lung cancer in humans (Shimada et al. 1998). 

Sanders If you get rid of the interstitial cells there is no further response to nerve stimulation. You can get a nice response to acetylcholine. Then you go back to the wild-type animal and you can block the breakdown of acetylcholine and then get a smooth muscle response. The point is that while there are synaptic connections in GI smooth muscle, synaptic connections between the motor neurons and smooth muscles are not so common. The major synaptic connections are between the motor neurons and the interstitial cells. 

Bolton I call interstitial cells of Cajal (ICCs) a type of smooth muscle. 

Sanders They release acetylcholine to the same extent. We measured the output of acetylcholine from the nerves, and this was the same in wild-type and mutant animals. It appears that the close association between the nerve terminals and the interstitial cells is very important. As acetylcholine is released, it is broken down by the esterase. If the esterase is inhibited, a response in the smooth muscle can be seen, but this is not physiological. 

Hirst That reflects Ca2+ cycling in the interstitial cells. 

Testicular interstitial cell tumors occur spontaneously in aged rats, and the incidence can vary greatly in control groups. This tumor is believed to be hormonally mediated. There was no evidence of malignancy in three rat studies and no evidence of this type of tumor in mice. It can be concluded that the tumorigenic effect, if real, is most unlikely to be relevant to human exposure [13]. 

The next largest pool is the liver [26], where the highest concentration is found in the periportal areas. Other organs in which mercury is likely to accumulate are the mucous membranes, the epithelium of the skin, the spleen, the interstitial cells of the testicles, and some parts of the brain. 

McKay, C.M. and Huizinga, J.D. (2006) Muscarinic regulation of ether-a-go-go-related gene K+ currents in interstitial cells of Cajal. The Journal of Pharmacology and Experimental Therapeutics, 319, 1112-1123. 

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