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Abstract: Even though the erythroleukemia cell lines K562 and HEL do not express α1-adrenoceptors, some α1-adrenergic drugs influence both survival and differentiation of these cell lines. Since Ca2+ is closely related to cellular homeostasis, we examined the capacity of α1-adrenergic drugs to modulate the intracellular Ca2+ content in K562 cells. Because of morphological alterations of mitochondria following α1-adrenergic agonist treatment, we also scrutinized mitochondrial functions. In order to visualize the non-adrenoceptor binding site(s) of α1-adrenergic drugs in erythroleukemia cells, we evaluated the application of the fluorescent α1-adrenergic antagonist BODIPY® FL-Prazosin. We discovered that the α1-adrenergic agonists naphazoline, oxymetazoline and also the α1-adrenergic antagonist benoxathian are able to raise the intracellular Ca2+-content in K562 cells. Furthermore, we demonstrate that naphazoline treatment induces ROS-formation as well as an increase in Δψm in K562 cells. Using BODIPY® FL-Prazosin we were able to visualize the non-adrenoceptor binding site(s) of α1-adrenergic drugs in erythroleukemia cells. Interestingly, the SERCA-inhibitor thapsigargin appears to interfere with the binding of BODIPY® FL-Prazosin. Our data suggest that the effects of α1-adrenergic drugs on erythroleukemia cells are mediated by a thapsigargin sensitive binding site, which controls the fate of erythroleukemia cells towards differentiation, senescence and cell death through modulation of intracellular Ca2+. [Copyright &y& Elsevier]

Background/aim: Medullary thyroid carcinoma (MTC) is a tumor associated with poor prognosis since it exhibits high resistance against conventional cancer therapy. Recent studies have shown that quinazolines exhibit a pro-apoptotic effect on malignant cells. The aim of the present study was to elucidate whether MTC cells are affected by quinazolines, in particular prazosin., Materials and Methods: Proliferation, apoptosis and cell morphology of the MTC cell line TT were analyzed by WST-1 assay, caspase 3/7 activation tests and microscopy. Fibroblasts were used as control for non-malignant cells., Results: Prazosin potently inhibited the growth of TT cells, induced apoptosis and caused vacuolization, as well as needle-like filopodia. Fibroblasts were affected by prazosin in the same way as MTC cells., Conclusion: MTC cells are responsive to prazosin treatment similar to other malignancies. The fact that fibroblasts also respond to prazosin further highlights the importance to identify the unknown pro-apoptotic target of quinazolines., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Neuroendocrine tumors are relatively insensitive to radiation therapy, as well as chemotherapy. Thus, new approaches for alternative therapies are needed. We found that glutamate receptor antagonists are capable of suppressing tumor growth and cell activity of different peripheral malignancies. In the present article we review scientific literature in this field of science. Subtype-specific, non-competitive, metabotropic glutamate receptor-1 antagonists differently suppressed the growth and metabolic cell activity of one human medullary thyroid carcinoma cell line, as well as of four different human midgut neuroendocrine tumor cell lines. Furthermore, PCR analyses revealed that this subtype of glutamate receptor is expressed in these cell lines. These first results indicate that specific metabotropic glutamate receptor antagonists suppress the proliferation and cell activity of neuroendocrine tumor cells, which makes them possible targets in cancer therapy.

In order to assess possible renal mechanisms causing the as yet unexplained side-effects of peripheral edema, weight gain and swollen limbs seen during the chronic administration of opioids in patients, a rat study was designed, mimicking a constant infusion (24 h) of morphine (CAS 57-27-2) using subcutaneous drug delivery device systems. Subcutaneous (s.c.) morphine infusions (0, 10, 30 mg/kg body weight/24 h) have been administered using implantable mini-osmotic pumps with a delivery rate of 10 microl/h. In addition, s.c. implantable inulin/PAH clearance depot systems were used in order to measure renal functions such as glomerular filtration rate (GFR = inulin clearance), renal plasma flow (RPF = PAH clearance), creatinine clearance and urea clearance in the conscious rat. Compared to controls, morphine caused an increase in PAH clearance, creatinine clearance (both dose dependent), urea clearance (higher dose), body weight, and urine potassium concentration (both groups). Urine minute volume was reduced in the 10 mg morphine group, a dose dependent highly significant decrease of urine sodium in the 30 mg morphine group compared to controls and a significant decrease compared to the 10 mg group could be found. Serum sodium was highly significant and food uptake was significantly increased in the 30 mg group compared to controls. The histological examination of kidneys revealed no differences among the various groups. These data indicate a role of the kidney in the induction of peripheral edema during permanent morphine administration.

Aim: Lornoxicam is a non opioid analgesic belonging to the oxicam group. The aim of this study was to determine whether lornoxicam has a preemptive analgesic effect., Methods: This study was carried out in a randomized, double-blind fashion with 66 patients divided into three groups undergoing gynecological operations. Group I was administered 8 mg of lornoxicam i.v. preoperatively followed by an 8-mg bolus every 8 h for a total dose of 24 mg in the first 24 h. Group II was administered 8 mg of lornoxicam i.v. bolus before the end of the operation followed by 8 mg every 8 h for a total dose of 24 mg in the first 24 h. Group III was administered placebo before and after the operation and for the first 24 h. The effectiveness was assessed postoperatively using the visual analogue scale (at rest, on exertion) and by calculating the total analgesic consumption of morphine hydrochloride in the first 24 h following operation. Vital signs and side effects were documented., Results: Groups I and II demonstrated significantly reduced pain scores compared to group III at various points in time. Group I also demonstrated a weakly significant reduction in analgesic consumption of morphine hydrochloride postoperatively compared to groups II and III., Conclusion: Lornoxicam administered preemptively appears to improve the quality of postoperative analgesia and lead to reduced consumption of opioid analgesics postoperatively in patients undergoing gynecological operations.

Experiences with long-term intraspinal infusion of opioid drugs using the new implantable medication pump VIP 30 in patients with chronic non-malignant pain are reported. During a 19-month period 10 patients with chronic pain--mainly mixed nociceptive-neuropathic pain--underwent implantation of the medication pump for long-term treatment. The mean follow-up period was 9.5 months. Pain relief was classified as very good in 22.2%, good in 44.4%, moderate in 22.2% and poor in 11.1%. In 88.9% of the cases the patients stated they would undergo the same procedure again. Technical problems (catheter dislocation) developed in 1/10 patients could be surgically corrected. One pump including catheter was explanted because of an infected seroma within the pocket area. Long-term intrathecal application of opioids with the VIP 30 pumps is an effective and safe treatment in patients with chronic non-malignant pain.

The present paper deals with the evaluation of normal heparin and low-molecular mass heparin as to their use in a new implantable medication pump. Latest versions of different Pharmacopoeias recommend techniques, which require large sample volumes for aqueous injectable drug solutions. Therefore, a commercially available enzymatic kit was used to determine heparin activity. As this test is designed for heparin plasma levels, transformation of the chromophore occurred only after adding heparin AT III complex, which is usually present in plasma. The applied test was found to be suitable regarding reproducibility, selectivity and sensitivity. There was no loss of enzyme activity of both normal heparin and low-molecular mass heparin within an investigation period of 8 weeks; thus, no decomposition products are to be expected and the biocompatibility of pump materials with both tested heparin preparations is evident.

This paper reports the results of experiments designed to determine the effect of linotroban (CAS 141443-73-4) a selective thromboxane (TXA2) receptor antagonist with novel antithrombotic activity, on renal function in conscious male and female rats. Linotroban was administered subcutaneously at doses of 0, 6, 24, 48 and 96 mg/kg/24 h by osmotic minipumps over 6 days. Inulin (Inutest) and para-aminohippuric acid (PAH) clearances were determined on the last day of linotroban treatment. These agents were delivered by a slow release tablet planted s.c. five days after the start of the linotroban treatment. Linotroban did not significantly alter renal functions, although there was a significant difference in GFR (glomerular filtration rate) for male and female rats receiving the highest dose. Linotroban is well tolerated but the difference in renal function between male and female rats at the highest dose may reflect a threshold of renal tolerance.

Studies were performed with a pump designed as a flow regulated implantable pump with a reservoir of 30 ml (VIP 30) for the continuous long term drug application in out-patients. The device consists of a gas driven two-chamber system containing the drug solution in one chamber and the propellant in the other. At body temperature the propellant underlies an isobaric expansion, thus creating pressure towards the impermeable, flexible membrane that separates the two chambers. Subsequently the pharmaceutical preparation is transported via a catheter to the target organ. With regard to its use as an implantable medication pump, four such devices were filled with solutions of morphine, baclofen, floxuridine, and fluorouracil, while one blank was filled with sterile water. The stability of the solutions and their compatibility with the pump materials was then examined. With a delivery rate of 1 ml/24 h, the pump is completely emptied after 30 days. Storage was at 37 degrees C and a number of values were obtained during the twice-normal period of 8 weeks; the content of active substances as well as any other products that had developed was determined with an optimized HPLC method. The chromatographic separations were done with two different eluents per substance. For each substance, individual samples from different periods of time were also chromatographed for up to 1 h and scanned at different wavelengths. All four pharmaceutical solutions were found stable after 30 days, only floxuridine showed a decomposition product after 7 weeks' storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Implantable coated Eudragit matrix tablets containing adrenaline in various concentrations should overcome the problem of additional handling stress during long term infusions. The efficiency of those tablets was tested in vitro, as well as in vivo using labeled adrenaline. Both in vitro and in vivo testing yielded satisfactorily output rates up to 20 h whereby the liver and serum content of 14C-fragments served as an additional prove for the postulated mode of action. Good correlation has been found between the mentioned out-put rates and adrenaline serum levels (measured according to Da Prada).

A new method has been developed for the simultaneous measurement of Inulin and PAH clearance in small laboratory animals (rats). An implantable Inulin/p-aminohippuric-acid matrix-retard tablet based on Eudragit was tested with the purpose to estimate renal clearances. Sufficiently high serum and urine levels of both substances can thus be maintained up to 12-48 hours. The advantage of the method is that it can be used for renal clearance tests in small conscious animals, able to move freely within their cages without serious handling stress.

Rats were exposed to electrostatic fields of different intensities and exposure times, after which the osmolality of the serum and the concentration of neutral fat and cholesterol in the serum were measured. The triglyceride and cholesterol concentrations of the sera were independent of the strength of the electrostatic field and independent of the length of exposure of the animals in the constant field or Faraday cages. They always lay within normal limits, but moved according to the conditions of the constant field: the neurtal fat concentrations to the upper, and the cholesterol concentrations to the lower limit. The differences compared to the controls could be confirmed statistically.

An intraperitoneal depot capsule was developed to improve the hitherto used in vivo test methods for chronic action of water soluble substances (repeated injections or permanent infusion which immobilizes the experimental animals). The capsule allows free movement of the animal and guarantees long-term continuous output of the substance. The effectiveness of the capsule was examined using adrenaline as test substance. In these experiments the maximum period of effectiveness and the consequences of permanent occupation of the receptors due to continued supply of adrenaline were studied.

A prototype is presented of a new, implantable therapeutic system for parenteral long-term administration of drugs. It consists of a casing with two chambers separated by a membrane. One of the chambers contains the dissolved substance and includes an interchangeable device to expel the substance. This chamber can be refilled transcutaneously through an opening which is then reclosed. The other chamber contains an isobarically expandable propulsive substance which exerts pressure upon the membrane to cause the solution to be expelled. The liberation time depends upon the particular expelling device used and the viscosity of the medicinal solution. The pharmaceutical and technological aspects of the applicability of this prototype in vitro are examined and discussed.

A combined method of tissue culture and storage in liquid nitrogen is described, which is suitable for covering the root surface of transplantable teeth with a dense cell layer: after an initial period of 10 days in tissue culture the teeth are stored in liquid nitrogen. 10 days before a transplantation the teeth are thawed and cultured again for 10 days. By this pretransplantation treatment a densely grown periodontal cell layer as well as an unlimited storage time are achieved.

Investigations were performed with the aim of establishing the influence of various environmental conditions (such as steady field conditions, climatized laboratories, Faraday's cage) on a number of enzymic activities in the rat (including glutamic oxaloacetic tic transaminase, glutamic pyruvic transaminase, lactic dehydrogenase, gamma-glutamyl transpeptidase, acid phosphatase), as well as the serum concentrations of triglycerides, the oxygen consumption of hepatic parenchyma cells, and the influence on the incorporation of 3H-thymidine (following partial hepatectomy). In the steady field, the activities of the cytoplasmic enzymes (GOT, GPT, LDH) were higher then under Faraday conditions. The same applies both to the hepatic oxygen consumption and to the neutral fat serum levels. The control values always remained within the range of the results obtained under steady field or Faraday conditions. In the structure-linked enzymes (gamma-glutamyl transpeptidase, acid phosphatase) the results were not uniform. Following partial hepatectomy, and under steady field conditions, the serum triglyceride concentrations showed a less pronounced drop than they did in the controls. Under selected environmental conditions, the results obtained lie within the physiological range. The present findings, therefore, do not permit definite conclusions to be drawn on favourable or unfavourable effects exerted by the different types of electroclimates.

The authors have developed a method for long-term permanent application of water soluble substances by a intraperitoneal depot capsule [KLINGENBERG et al., Exp. Path. 13, 302-311 (1977)]. The present study deals with the effects on the liver and several metabolic processes induced by continuous long-term adrenaline application by means of such a depot capsule.

During an acute inflammation, the blood levels of noradrenaline, dopamine and insulin increase uniformly until the fourth day, then reach a climax which for dopamine is above the norm, while the suppressed levels of noradrenaline and insulin approach the norm. All values decrease on the fifth day (end of the experiment). Glucose behaves inversely, showing a minimum on the fourth day. Corticosterone displays two peaks, on the first and fourth days. The adrenaline level differs distinctly from these patterns: it is elevated on the second, fourth and fifth days. By releasing each catecholamine independently, the organism can possibly influence the course of the inflammation.

A 24 h lasting long term adrenaline application in the form of subcutaneously implanted retard-tablets causes functional and morphological changes in the kidney, which are dose dependent and either reversible or irreversible. Animals in the V 15 group received one 15 mg and in the V 30 group two 15 mg adrenaline tablets resp. The tablets were removed after 24 h and a clearance depot capsule was implanted in the abdominal cavity. The test period extended from 22 h after removal of the retard tabl. to 21 d thereafter. Inulin (except the V 30 grp.), PAH and urea clearance are showing no significant differences. The data of urine gamma-GT activity, urea and urea-N in serum and urine, S-glucose, S-triglycerides, Combur-8-test, Na+ and K+ levels are in normal ranges. Morphological changes were found in the glomerula and tubular regions. Both the number of damaged nephrons and the extent of the damage depend upon the doses of adrenaline given. All glomerula with visible serious changes are irreversibly damaged; this was not true in case of the tubule. In the latter, after 7 d, the fatty deposits had diminished or disappeared.

Under the conditions of pair feeding, water-deprived rats predominantly use fat as a metabolic fuel, whereas total energy turnover as measured by oxygen consumption is not altered. Plasma free fatty acids are elevated in dehydrated rats, indicating enhanced lipolysis. Reduced hepatic fatty acid synthesis and reduced triacylglycerol secretion into the blood seem to be the main factors for the decrease of plasma triacylglycerol, observed 48 hours after the onset of water deprivation. Enhanced plasma levels of corticosterone (about 100%) and glucagon (about 50%) may contribute to the metabolic situation observed in water deprivation.

To be able to study the long-term effects of moderately enhanced catecholamine levels in rats, we developed subcutaneously implantable retard systems, granting a linear output of various agents throughout the test time. Adrenaline application leads to hyperglycemia without elevation of serum immune-reactive-insulin (IRI) during 20 h of uninterrupted adrenaline (A) action. This we call an A-induced diabetes like reaction. It could be completely abolished by simultaneous application of low phentolamine (Regitin) doses. Simultaneous application of propranolol (P) gradually diminished blood glucose levels from about 200 mg/dl after 6 h to 120 mg/dl after 20 h. Since here insulin levels are uniformly low, decline of blood glucose could not be due to enhanced insulin-action. The moderate hyperglycemia after 6 h isoprenaline (ISO)-treatment alone goes with a hyperinsulinemia at the same time. Obviously this hyperinsulinemia cannot cope with the increased blood glucose probably due to enhanced liver-glycogenolysis by intact alpha-action. Later on insulin--despite of beta-action on pancreas--declines strictly proportional with diminishing blood-glucose-levels. A comparison between the action of catecholamines and their blockers showed that alpha-blockers tend to diminish blood glucose levels by two independent ways, namely by the inhibitory action on pancreas and the inhibitory action on liver glycogenolysis.

The effects of adrenaline (A) on liver T3 and rT3 neogenesis from T4 were studied in Wistar rats. The animals were implanted subcutaneously either with A or placebo (P) especially coated tablets which linearly released the hormone. The serum A values 6 hrs after implantation of 7.5, 15.0 and 45.0 mg tablets were 6.5 +/- 1.31, 6.8 +/- 1.8 and 16.4 +/- 1.9 ng/ml, respectively vs 4.4 +/- 2.5 ng/ml seen in P pretreated group. The output rates of A were 0.11 (7.5 mg), 0.18 (15 mg) and 0.52 microgram/ml (45 mg). The pretreatment with A led to hyperglycemia and the "low T3 syndrome". Neogenesis of T3 from T4 in medium containing liver microsomes of P pretreated rats was 5.49 +/- 0.25 pmol of T3/mg protein/min and decreased in A pretreated rats to 3.82 +/- 0.17, 3.12 +/- 0.27 and 3.06 +/- 0.11 pmol of T3/mg of protein/min. Neogenesis of rT3 from T4 in microsomes from P group was 1.52 +/- 0.09 pmol rT3/mg protein/min and increased after A to 2.71 +/- 0.11, 2.60 +/- 0.21 and 2.21 +/- 0.34 pmol of rT3/mg protein/min thus showing no dose dependency. Enrichment of microsomes medium with cytosol either from P or A pretreated rats had no effect on T3 generation thus excluding effect of A on cytosolic cofactor. Although cytosol further increased rT3 neogenesis this was seen regardless of whether cytosol was obtained from A or P implanted rats. It is concluded that A decreases the activity of T4-5'-deiodinase in liver, and possibly increases the activity of T4-5-deiodinase.