Topical PUVA, etretinate, and combined PUVA and etretinate for palmoplantar pustulosis: comparison of therapeutic efficacy and the influences of tonsillar and dental focal infections

Twenty patients with palmoplantar pustulosis (PPP) were treated with topical PUVA, oral etretinate (Re), or combined PUVA and etretinate (Re-PUVA). Re and Re-PUVA treated sites improved and/or cleared more rapidly than PUVA treated sites. Complete clearance was observed in six of ten sites treated with Re-PUVA, two of ten with Re, and one of ten sites with PUVA within 12 weeks. UVA-control sites failed to be cleared within 12 weeks. Remission periods after stopping the treatment were 1.5 +/- 0.5 weeks (n = 2) with Re, 10.5 +/- 11.4 weeks (n = 6) with Re-PUVA, and one year (n = 1) with PUVA. These results overall suggested that Re-PUVA is the most effective treatment for PPP. Tonsillar focal infection (TFI) and dental focal infection (DFI) were found in 6/20 and 17/20 patients, respectively. However, the presence of focal infection (FI), TFI and/or DFI, did not appear to interfere with the therapeutic activities of Re and/or PUVA, because the complete clearance rates and remission periods in FI(+) patients were comparable with those in FI(-) patients.

Polyprenoic acid, E-5166, is effective in inhibiting the proliferation of keratinocytes in vitro

E-5166 is a newly synthesized polyprenoic acid that has been reported to control epithelial differentiation and to have antiproliferative effects on various tumor cells in vitro. This study examined the effects of E-5166 on the proliferation of keratinocytes. Three kinds of keratinocytes were used: normal human keratinocytes, a human trichilemmoma-derived K-TL-1 cell line, and a Pam 212 cell line. Cell proliferation was measured by 3H-thymidine incorporation and also by determining cell numbers. E-5166 was found to have significant antiproliferative effects on each of the cell lines studied. When Pam 212 cells were cultured in the presence of E-5166, cell proliferation was inhibited in a dose-dependent fashion. The inhibitory effect appeared to be reversible, since removal of E-5166 from the culture medium resulted in a subsequent return of cell proliferation. For normal human keratinocytes and K-TL-1 cells, E-5166 inhibited 3H-thymidine incorporation in a dose-dependent fashion. Furthermore, E-5166 showed significantly stronger antiproliferative capacity than Ro 10-9359, one of the aromatic retinoids, on Pam 212 cells and normal human keratinocytes.

Neuropharmacological profile of V-9-M, a putative neuropeptide derived from procholecystokinin

(1) The present review suggests that V-9-M, a putative neuromodulator derived from pro-CCK, possesses apparent sedative actions and prevents experimental amnesia in both passive and active avoidance paradigms in rats. (2) These properties are similar to CCK-8, but some differences were noticed; (i) CCK-8 is a potent appetite inhibitor, while V-9-M does not affect food intake in fasted rats, and (ii) small doses of apomorphine cause hypomotility which is abolished by CCK-8, while V-9-M decreases the motility further. (3) More important is the fact that peripheral administration of CCK-8 produces central actions, but that of V-9-M is ineffective. (4) Although CCK-8 and V-9-M are derived from the same pro-CCK, their chemical structures are quite different, and the receptors for these two peptides are not the same. (5) CCK-8 has both central and peripheral receptors, but the presence of a peripheral receptor for V-9-M is questionable. (6) The different properties may be partially explained by this. (7) However, immunochemical studies indicated the coexistence of CCK and GABA in the cortical neurons. (8) This suggests that V-9-M may be present in the GABA neurons together with other CCK fragments. (9) There might be close interaction between V-9-M and the GABAergic system.

Memory effect of caerulein and its analogs in active and passive avoidance responses in the rat

The memory effects of caerulein (CER) and its analogs ([des-Gln2]-CER and [Leu5,Nle8]-CER) were compared with that of cholecystokinin octapeptide (CCK-8) using active and passive avoidance responses in rats. In the active avoidance test, single subcutaneous (SC) injection of CER and its analogs immediately after the learning trials at doses of 10 and 100 ng/kg prevented extinction of learned task for 10 days, and at a dose of 1000 ng/kg for at least 15 days, but the effect of CCK-8 was somewhat weaker. In the saline control group, the number of responses decreased after 5 days. In the passive avoidance response, electroconvulsive shock (ECS)-induced amnesia was partially prevented by CCK-8 at doses of 100 and 1000 ng/kg SC, while CER and its analogs at doses of more than 100 ng/kg totally prevented the ECS-induced amnesia. Intraperitoneal administration of scopolamine caused complete amnesia which was also partially prevented by CCK-8, while CER could totally prevent the amnesia following SC injection of 2 micrograms/kg. These results indicate that CER and its analogs are more effective than CCK-8 for preventing experimental amnesia.

Muscarinic-stimulated norepinephrine release and phosphoinositide hydrolysis in PC12 cells are independent events

This laboratory has reported recently that muscarinic receptor-stimulated release of norepinephrine from pheochromocytoma (PC12) cells is dependent upon an influx of Ca2+ through a Ca2+ channel that is regulated by a pertussis toxin-sensitive GTP-binding protein (G-protein) (Inoue, K., and Kenimer J. G. (1988) J. Biol. Chem. 263, 8157-8161). In the present study, we have examined the role of phosphoinositide hydrolysis in this mechanism. The muscarinic agonist methacholine was shown to stimulate phosphoinositide hydrolysis by a mechanism that was sensitive to pertussis toxin inhibition. When assayed in the absence of Ca2+, muscarinic-stimulated norepinephrine release but not phosphoinositide hydrolysis was blocked. Conversely, muscarinic-stimulated phosphoinositide hydrolysis but not norepinephrine release was blocked in cells preincubated with phorbol 12,13-dibutyrate. In contrast to several previous hypotheses that suggested that muscarinic-stimulated neurotransmitter release is dependent upon phosphoinositide hydrolysis, our results suggest that these two muscarinic-stimulated processes are independent events in PC12 cells. Inhibition studies with muscarinic receptor subtype-specific antagonists suggest that norepinephrine release is regulated by an M2 subtype muscarinic receptor and that phosphoinositide hydrolysis is regulated by an M3 subtype muscarinic receptor.

Neuropharmacological properties of V-9-M, a putative neuropeptide derived from procholecystokinin, in the rat

It has been suggested that a nonapeptide called V-9-M (Val-Pro-Val-Glu-Ala-Val-Asp-Pro-Met) is produced by the processing of procholecystokinin. However, its physiological and pharmacological activities are not known. In the present study, synthetic V-9-M amide was injected into the lateral ventricle of the rat and its effects on general activities were observed. V-9-M caused a marked sedation; it suppressed spontaneous activity and hypermotility induced by thyrotropin-releasing hormone, methamphetamine, and apomorphine. Hypomotility induced by small doses of apomorphine was also decreased further. V-9-M caused hypothermia and prolonged the duration of pentobarbital-induced sleep, and it decreased locomotion in an open-field situation. However, V-9-M did not affect appetite in fasted rats.

Effect of V-9-M, a peptide fragment derived from procholecystokinin, on memory processes in the rat

It has been reported that a nonapeptide (Val-Pro-Val-Glu-Ala-Val-Asp-Pro-Met) called V-9-M is produced from procholecystokinin in the brain. Since this peptide is particularly abundant in the hippocampus, septum, and amygdala. V-9-M may be involved in memory processes. The present study was attempted to observe the effect of V-9-M on memory processes of rat performing a one-trial passive avoidance task and a platform jumping active avoidance task. The results indicate that injection of V-9-M into the lateral ventricle of the rat prevents experimental amnesia induced by electroconvulsive shock in passive avoidance testing, and that this effect is not significantly affected by cholecystokinin-8 antagonists. V-9-M also causes a long-lasting enhancement of memory in the active avoidance task. These results suggest that V-9-M may participate in the facilitation of memory.

Thy-1+ dendritic epidermal cells in mice: precursor frequency analysis and cloning of concanavalin A-reactive cells

Bulk cultures of mouse Thy-1+ dendritic epidermal cells (Thy-1+ DEC) have been shown to proliferate in response to concanavalin A (Con A) and IL-2, to secrete IL-2-like growth factors, and to lyse target cells such as YAC-1. Limiting dilution microculture was utilized in order to determine the precursor frequency of Con A-responsive Thy-1+ DEC in suspensions of AKR/J epidermal cells as well as whether these several functional activities all reside within a single Thy-1+ DEC precursor. Precursor frequency analysis of cultures established with limiting numbers of FACS-purified Thy-1+ DEC, irradiated syngeneic splenic filler cells and exogenous IL-2 indicated that approximately 20% of Thy-1+ DEC proliferated in response to Con A. Parallel microcultures in which purified Thy-1+ DEC were plated at a density of 0.5 cells/well were used to establish clones. Twenty clones were characterized phenotypically, and ten of these were also tested for their capacities to proliferate in response to Con A or IL-2, to secrete IL-2-like growth factors, and to exhibit cytotoxicity. All clones were Thy-1+ and L3T4-, but while most were also Lyt-2-, several contained 3%-18% dull Lyt-2+ cells. Functional studies revealed that each clone displayed all of the above functional activities, albeit with substantial quantitative variation. Clones with the highest cytotoxic activity had relatively low responsiveness to Con A or IL-2 and included all clones containing dull Lyt-2+ cells; conversely, clones with the highest proliferative responses had relatively low cytotoxic activity and were all Lyt-2-. This degree of functional and phenotypic heterogeneity among cloned Thy-1+ DEC may reflect their particular states of activation or differentiation; whether it reflects the biologically relevant in vivo activities of these cells must still be determined.

Effect of cholecystokinin tetrapeptide amide on the metabolism of 5-hydroxytryptamine in the rat brain

The effect of cholecystokinin tetrapeptide amide (CCK-4) on the content of 5-hydroxytryptamine (5-HT) and its major metabolite, 5-hydroxyindole-3-acetic acid (5-HIAA), was studied in various regions of the brain of rat. After intracerebroventricular administration of CCK-4, the content of 5-HT decreased, while the content of 5-HIAA increased in some areas. These changes were marked 30 min after the injection and relatively small doses (10 and 100 ng) of CCK-4 produced a pronounced effect, but larger doses (1 and 10 micrograms) were less effective. The ratio of 5-HIAA/5-HT increased significantly in most regions of the brain, except in the striatum and the olfactory tubercle. The results indicate that exogenous CCK-4 in small doses stimulates the metabolism of 5-HT in the brain of rat.

Effect of vasoactive intestinal peptide on dopaminergic system in the rat brain

The present study analyzed the effect of vasoactive intestinal peptide (VIP) on the content of dopamine (DA) and its main metabolite, DOPAC, in the rat brain. Intracerebroventricular administration of VIP increased the DA and DOPAC content, causing a dose-dependent increase in the DOPAC/DA ratio in various regions of the brain. The results suggest that VIP facilitates the DA metabolism in the brain.

Interactions of cholecystokinin, beta-endorphin, and their antagonists on passive avoidance behavior in rats

The effects of cholecystokinin octapeptide (CCK-8), cholecystokinin tetrapeptide amide (CCK-4), beta-endorphin, proglumide, and naloxone on passive avoidance behavior were studied in rats. Intracerebroventricular (i.c.v.) injection of beta-endorphin (1-10 micrograms) had no significant influence on the latency of the avoidance response in intact rats. Also, beta-endorphin (0.05-5 micrograms, i.c.v.) did not affect the response in rats treated with electroconvulsive shock (ECS). The preventive effect of CCK-8 (0.1-1.0 micrograms, i.c.v.) on ECS-induced amnesia was partly antagonized by beta-endorphin (0.05-10 micrograms, i.c.v.). Intraperitoneal (i.p.) injection of naloxone (1-10 mg/kg) could not prevent ECS-induced amnesia, but continuous subcutaneous infusion of this drug (2 mg/day, 7 days) completely abolished the amnesia. Naloxone (1 and 10 mg/kg, i.p.) also partly antagonized amnesia induced by proglumide (1 and 10 micrograms, i.c.v.) and prevented it when induced by CCK-4 (5 and 10 micrograms, i.c.v.). The results indicate the facilitating action of naloxone and the inhibitory effect of beta-endorphin on memory, suggesting that the endogenous opiate systems are involved in some way in the memory processes.

Nicardipine-sensitive enhancement of high K+ -evoked dopamine release in PC12 cells pretreated with 12-O-tetradecanoylphorbol 13-acetate

The effects of the phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA) on stimulus-evoked dopamine release were studied in PC12 cells. Pretreatment of the cells with TPA resulted in an enhancement of dopamine release which could be further stimulated by high concentrations of K+, A23187, but not with carbamylcholine. TPA-dependent, high-K+ -evoked enhancement of dopamine release was studied in detail: a maximum release was observed (169% of control) in response to 50 mM KCl upon treatment with 10(-7) M TPA for 5 min at 37 degrees C. This enhancement of dopamine release was associated with the concomitant reduction of the concentration rise of intracellular Ca2+ ([Ca2+]i) induced by a high concentration of K+ monitored by a fluorescent indicator, fura2. Thus, these data provide an example for alteration in the efficiency of stimulus-secretion coupling as pointed out in our previous paper. Moreover, we have shown that nicardipine, CdCl2, and CoCl2 inhibit high-K+ -evoked dopamine release more effectively in TPA treated cells than that of untreated cells, and that the TPA-dependent, high-K+ -evoked dopamine release observed in TPA treated cells is completely abolished by the presence of nicardipine, Cd2+ or Co2+, but is only partially inhibited in the presence of verapamil. These relevant findings suggest the possible involvement of protein kinase C in regulating the efficiency of a high-K+ -evoked dopamine release through the modification of nicardipine-sensitive Ca2+ channels.

Disposition of moxalactam and N-methyltetrazolethiol in rats and monkeys

The disposition of moxalactam (MOX) and N-methyltetrazolethiol (NMTT) in rats and monkeys after intravenous injection was investigated, focusing on the in vivo liberation of NMTT, by using [NMTT-14C]MOX and [14C]NMTT. After [NMTT-14C]MOX injection, MOX levels in plasma quickly became high in both rats and monkeys and then declined, with half-lives at the beta phase of 18.8 and 67.1 min, respectively. The levels of NMTT liberated from MOX were much lower than those of MOX, but the apparent elimination was significantly slow. The levels of MOX and NMTT in rat liver were almost comparable but lower than those in plasma. With [14C]NMTT administration, the level of NMTT in plasma declined, with half-lives at the beta phase of 21.5 min in rats and 54.0 min in monkeys. After [NMTT-14C]MOX injection, most of the radioactivity was excreted in urine as MOX, with 11% of the dose in rats and 8% of the dose in monkeys eliminated as NMTT until 24 h. Total biliary excretion was 26% of the injected radioactivity in rats, and most of it was due to MOX. In one monkey, the total biliary excretion was only 0.2% of the injected radioactivity. With [14C]NMTT administration, most radioactivity was excreted in the urine as unchanged NMTT in both animals. Oral administration in rats showed that part of the biliary-excreted MOX was degraded to NMTT in the intestine and then absorbed. Repeated administration of [NMTT-14C]MOX to rats did not change the levels of MOX and NMTT in plasma or liver nor did it change the excretion profiles. Thus, accumulation of MOX and NMTT did not occur.

Regulation of T-cell receptor gamma-chain RNA expression in murine Thy-1+ dendritic epidermal cells

The epidermis of normal mice contains two distinct populations of dendritic cells derived from the bone marrow, Ia+ Langerhans cells and Ia- cells that express the Thy-1 alloantigen. The Thy-1-bearing dendritic epidermal cells (Thy-1+ dEC) have a surface phenotype similar to that of very early T-lineage cells, produce IL-2-like growth factors and exhibit cytotoxicity which is not restricted by the major histocompatibility complex (MHC). The relationship of Thy-1+ dEC to the T-cell lineage is unclear. Most T lymphocytes bear a receptor for antigen composed of an alpha chain and a beta chain associated with a nonpolymorphic complex termed CD3 (T3). A minor population carries a receptor in which CD3 is associated with a gamma/delta complex. We have analysed clones of Thy-1+ dEC for rearrangement and expression of the genes for the alpha-, beta- and gamma-chains of the T-cell receptor (TCR). They do not express alpha or beta but do carry a gamma/delta complex. Activation of the cells with Con A is associated with a rapid decrease in the steady-state level of gamma-chain RNA. Because Thy-1+ dEC resemble early stage T lymphocytes, down-regulation of TCR expression may reflect a necessary event during T cell differentiation.

Activation of keratinocyte fibronectin receptor function during cutaneous wound healing

Keratinocytes freshly isolated from unwounded skin could not attach and spread on fibronectin (FN)-coated culture dishes and could not bind and phagocytose FN-coated beads. These adhesive functions were activated, however, in keratinocytes that were isolated from healing wounds. Moreover, adhesiveness of basal keratinocytes to FN substrata was activated during epidermal cell or explant culture. Activation was specific for attachment to FN compared to other adhesion ligands, and occurred even when epidermal cells were cultured on collagen, basement membrane matrix, or lectin-coated substrata. Biochemical studies showed that keratinocytes have a 140 x 10(3) Mr FN receptor analogous to the fibroblast receptor for FN, and that this receptor is expressed in activated keratinocytes but not in keratinocytes freshly isolated from unwounded skin. The absence of FN receptors from keratinocytes in unwounded skin is not surprising since the basal keratinocytes of the epidermis are attached to a basement membrane containing laminin and type IV collagen. During wound repair, however, these cells migrate over or through a FN-coated matrix. Consequently, expression of FN receptors may be an essential feature of healing. Believing that FN is the required substratum for keratinocyte migration during wound healing, we have initiated clinical studies to determine if topical application of FN is useful as a therapy for non-healing cutaneous ulcers.

Morphological appearance of epidermal cells cultured on fibroblast-reorganized collagen gels

Human foreskin fibroblasts were used to reorganize hydrated collagen gels into a dermal-like matrix, after which freshly isolated keratinocytes isolated from rabbit ear skin were placed on the surfaces of the matrices and cultured for up to 12 days. Transmission electron microscopy revealed 8-12 cell layers of epidermal cells organized in three distinct strata. The basal stratum consisted of cuboidal to columnar cells with typical complement of organelles, oval nuclei, and prominent tonofilaments inserting into desmosomes. Mitotic cells often were found at this level. There was no well-defined basement membrane region; rather, many of the cells appeared to be in close contact with collagen fibrils. The intermediate stratum of suprabasal cells consisted of elongated cells that had reduced organelles, but still were connected to each other by desmosomes. Finally, the superficial stratum of suprabasal cells contained cells that were completely flattened and often appeared to be sloughing off the apical surfaces of the cultures. Indirect immunofluorescence studies carried out on frozen sections revealed bullous pemphigoid antigen associated with basal epidermal cells; pemphigus vulgaris antigen around the epidermal cells of all strata, and keratin present in the epidermal cells of all strata. Filaggrin was observed in punctate and fibrillar arrangements in suprabasal cells. Fibronectin was found in a linear deposit at the dermal-epidermal junction and around the fibroblasts in the reorganized collagen gels. Type-IV collagen and laminin, however, were not detected.

[Differences in the immunostimulatory activity and antitumor therapeutic effect of OK-432 and N-CWS]

Immunobiological activities of OK-432 and N-CWS were studied in BALB/c-Meth-A and C3H-MH 134 systems. Peritoneal exudate cells obtained from mice injected i.p. with OK-432 or N-CWS showed stronger in vitro cytotoxicity against Meth-A and YAC-1 cells than did those from non-treated mice. Spleen cells from OK-432 or N-CWS-treated mice exhibited lower Con A mitogenic response in comparison with those from non-treated mice. When Meth-A or MH-134 tumor cells were admixed with OK-432 or N-CWS, the intradermally inoculated tumor cells showed no or slower growth than did those admixed with saline only. There were no significant differences in all the above mentioned activities between OK-432 and N-CWS, and there was no difference in the direct tumor inhibitory activity of the two agents in vitro. However, the administration of N-CWS had no therapeutic effect against i.p.-inoculated tumor cells while OK-432 showed a strong therapeutic effect by the same treatment schedule. Further studies are required to clarify the mechanisms responsible for the difference in the therapeutic effect of the two agents.

Cell cycle-dependent modulation of biosynthesis and stimulus-evoked release of catecholamines in PC12 pheochromocytoma cells

Catecholamine biosynthesis and its stimulus-evoked release in PC12 pheochromocytoma cells were studied as a function of cell cycle by means of HPLC with electrochemical detection. We found that 3,4-dihydroxyphenylethylamine (dopamine) levels in PC12 cells remained constant throughout the period of cell cycle. In contrast, the noradrenaline content was dependent on the cell cycle: it increased during the S + G2 phase followed by a decrease in the M phase. These results were confirmed further by measuring the activities catalyzing the catecholamine biosynthesis. Thus, activities of tyrosine 3-monooxygenase and 3,4-dihydroxyphenylalanine decarboxylase were independent of the cell cycle, whereas both soluble and membrane-bound dopamine beta-monooxygenase activities were modulated during the cell cycle. On the other hand, release of the catecholamines stimulated with 50 mM KCl increased in the G1 phase, reached a maximum in the late G1, and then gradually decreased in later periods. We also found that carbamylcholine-induced release of the catecholamines occurred maximally in the early S + G2 phase followed by a decrease during the M phase. Cell cycle dependence of the catecholamine release was in good agreement with that of 45Ca2+ uptake. Thus, this study provides evidence that the catecholamine biosynthesis and its release in PC12 cells are modulated during the period of cell cycle.

Activation of rabbit keratinocyte fibronectin receptor function in vivo during wound healing

Freshly isolated rabbit keratinocytes expressed low fibronectin (pFN) receptor function as shown by their poor ability to attach and spread on pFN-coated substrata or to bind and ingest pFN-coated beads. Following in vitro culture of these cells, however, pFN receptor function was activated. The cultured cells appeared to be normal, based on their ability to reepithelialize rapidly full-thickness cutaneous wound beds. Freshly isolated keratinocytes that had low pFN receptor function were autotransplanted onto full-thickness wound beds. Two days after transplantation, keratinocytes recovered from these wounds were observed to express increased pFN receptor function. This activity was maximal in keratinocytes isolated 3 days after transplantation and declined in keratinocytes isolated at later times. By 10 days after transplantation, the transplanted cells had formed a multilayered hyperplastic epidermis and reconstituted their laminin and type IV collagen-containing basement membrane. It is proposed that initiation of pFN receptor function in keratinocytes is a crucial mechanism necessary for them to attach to and migrate through the pFN-rich wound bed comprised of granulation tissue. After reepithelialization is complete, and the basement membrane re-forms, pFN receptor function declines markedly because it is no longer essential to the cells.

Relationship between dopamine content and its secretion in PC12 cells as a function of cell growth

The PC12 cell line derived from a rat adrenal medullary tumor is known to synthesize dopamine and to release it in response to cholinergic agonists or depolarizing agents. In this report, we have studied the relationship between dopamine biosynthesis and its stimulus-induced secretion in PC12 cells as a function of cell growth. The endogenous dopamine content was found to depend on cell growth, and reached a maximum in the stationary phase. This increase was associated both with an increase in the specific activity of tyrosine 3-monooxygenase, and with an increase of DOPA-decarboxylase in the cells. On the other hand, the maximal release of dopamine occurred in the late exponential phase before the endogenous dopamine was maximally synthesized in the cells. Moreover, the uptake of 45Ca2+ stimulated with either carbamylcholine or high K+ was also regulated by cell division: the maximal uptake took place in the same period of culture in which the maximal release of dopamine was observed. Thus, this report offers new evidence that the biosynthesis and secretion of dopamine are separately regulated in PC12 cells.

Fibronectin-mediated keratinocyte migration and initiation of fibronectin receptor function in vitro

Cell suspensions of human keratinocytes, freshly isolated from skin specimens, did not express plasma fibronectin (pFN) receptor function in short-term assays for cell attachment and spreading on pFN-coated culture dishes and binding and phagocytosis of pFN-coated latex beads. These activities were expressed, however, by the cells harvested from primary keratinocyte cultures after 2-4 days of culture. Analysis of the cell types arising during primary culture, based on staining with antikeratin antibodies and bullous pemphigoid (BP) serum, revealed that about 90% of the originally isolated cell population consisted of keratinocytes (keratin-positive) and 30% were basal cells (BP antigen-positive). After 2 days of culture, 95% of the cells were keratinocytes and 70% were basal cells. In vitro initiation of pFN receptor function also was observed in cells harvested from epidermal explants. After 9 days in culture, the cells that migrated out of the explants also were active in short-term cell adhesion assays, while cells remaining in the central region of the explant had much less activity. In related studies, the role of pFN in epidermal cell migration was analyzed, and it was found that anti-pFN antibodies inhibited migration of keratinocytes out of epidermal explants. Addition of preimmune IgG, however, had no effect. It appears, therefore, that pFN is important in all aspects of keratinocyte adhesion, and the expression of pFN receptor function may be a critical activation step necessary for basal cell phagocytosis and migration during wound healing.

Human keratinocyte adhesion and phagocytosis promoted by fibronectin

Epidermal cells from human foreskin or cadaver skin were found to bind and phagocytose fibronectin-coated latex beads but not serum albumin-coated beads. Three lines of evidence suggested that the beads actually were internalized by the cells and not bound only at the cell surfaces. First, the fibronectin coat on internalized beads could be detected with antifibronectin antibodies only if the cells were permeabilized prior to indirect immunofluorescence staining. Second, the internalized beads were not released from the cells by trypsin treatment. Finally, electron microscopic observations showed that the internalized beads were packaged individually and in clusters inside endocytic vesicles in the perinuclear region of the cells. These vesicles had the typical appearance of lysosomes, and, based on the release of trichloroacetic acid-soluble radioactive fragments of fibronectin into the incubation medium, it was concluded that degradation of the fibronectin on the bead surfaces occurred. The epidermal cells that phagocytosed the fibronectin-coated beads were confirmed as keratinocytes according to their electron microscopic appearance and prominent immunofluorescence staining with antikeratin but not anti-plasma fibronectin antibodies. Fibronectin also was found to promote the attachment and spreading of keratinocytes on culture dishes, although the concentration of fibronectin required for half-maximal activity (approximately 5 micrograms/ml) was severalfold higher than the concentration of fibronectin required for spreading of human fibroblasts (approximately 1 microgram/ml). The results suggest the possible importance of fibronectin in mediating adhesion and phagocytosis by keratinocytes, which may be important for the migration of these cells during wound repair.

Clonal variability of PC12 pheochromocytoma cells with respect to catecholamine biosynthesis

Clonal variants of PC12 cells with respect to catecholamine biosynthesis were isolated, and the catecholamine content was measured by high performance liquid chromatography with electrochemical detection. The dopamine content of 13 subclones, which were selected and isolated in tyrosine-free medium, was substantially higher than the control level: 0.91 +/- 0.10 nmol/mg protein (mean +/- SEM; n = 3). In contrast, the noradrenaline content showed a marked heterogeneity: only two subclones contained noradrenaline levels similar to or higher than the control level: 0.40 +/- 0.05 (n = 5). The rest of them contained below the level of 0.20, and only negligible amounts of noradrenaline were found in four subclones. Thus, the noradrenaline-to-dopamine ratio varied widely between 0.003:1 and 0.53:1. This divergence of the noradrenaline content appears to be related to differing levels of dopamine beta-monooxygenase activity. The administration of ascorbate to the medium alone, however, did not restore the level of noradrenaline to the normal level in a subclone. Heterogeneity of the response to applied glucocorticoid was also demonstrated.

Application of high-performance liquid chromatography to the study of esterified 7-dehydrocholesterol in rat skin

A novel and precise method for determining free and esterified 7-dehydrocholesterol in rat skin was developed by using a two-step high-performance liquid chromatography system. This method involves initial lipid extraction, separation of the free and esterified 7-dehydrocholesterol by, firstly, preparative high-performance liquid chromatography, saponification, and determination by, secondly, analytical high-performance liquid chromatography. This method was applied to the study of the 7-dehydrocholesterol in rat skin. Almost all of the 7-dehydrocholesterol in rat skin was present in an esterified form (78-93%). Ultraviolet exposure of the skin increased total 7-dehydrocholesterol content, however, the percentage of esterified 7-dehydrocholesterol was not altered appreciably. Application of this method to the study of the photo-metabolism of 7-dehydrocholesterol in rat skin revealed that almost all of the vitamin D3 produced by ultraviolet rays was in the esterified form.

[Placental transfer and distribution of betamethasone 17,21-dipropionate in various regions of the brain of pregnant rats and mice (author's transl)]

As betamethasone 17,21-dipropionate induces adrenal atrophy in rat dams and adrenal hypertrophy in the fetus, we investigated the placental transfer of this compound using autoradiography and liquid scintillation counting in animals in the late stages of pregnancy. In these two species, 3H-betamethasone 17,21-dipropionate and/or its metabolites transferred across the placental barrier into fetal tissues and were distributed at levels lower than detected in the maternal tissues. The rat fetus showed a high uptake of radioactivity in the adrenal cortex. In pregnant rats, the ratios of the radioactivity in the adrenal cortex. In pregnant rats, the ratios of the radioactivity in brain tissues to the plasma in fetuses were much higher than in the dams after the administration of 3H-betamethasone 17,21-dipropionate or 3H-betamethasone. In the dams given 3H-betamethasone 17,21-dipropionate, the accumulation of radioactivity in the hypothalamus and septum was significantly greater than in other regions. The present study suggests that betamethasone 17,21-dipropionate or its metabolites transferred across the placental barrier following administration to the mother rat may produce an adrenal hypertrophy in the fetus and that accumulation of radioactivity in the hypothalamus of the dam may be related to a suppression of the function of hypothalamo-pituitary-adrenal axis.

Serum and lymph lipids in rabbits with carbon tetrachloride-induced cirrhosis of the liver

Lymph flow and the composition of lymph lipids from the hepatic and thoracic ducts of rabbits with cirrhosis of the liver (induced by 46-51 intramuscular injections of a mixture of carbon tetrachloride and olive oil at 4-day intervals) have been compared with those of control animals injected with olive oil only. In cirrhotic animals, the concentration of lymph lipids was not greatly altered, but lymph flow, and consequently the hourly transport of lipids by lymph were greatly increased; the increase in transport of cholesteryl esters, free cholesterol, and phospholipids by way of the thoracic and hepatic duct lymph was particularly striking. The concentration of these lipid fractions in serum from the cirrhotic rabbits was also increased. The differences normally observed between lipid fatty acid compositions of serum and lymph disappeared in cirrhotic animals; this is interpreted as due to increased hepatic permeability to lipoproteins.