Hypericin fluorescence kinetics in the presence of low density lipoproteins: study on quail CAM assay for topical delivery.

There has been increasing interest in fluorescence-based imaging techniques in clinical practice, with the aim to detect and visualize the tumour configuration and the border with healthy tissue. Strong photodynamic activity of hypericin (Hyp) can be improved by various molecular transport systems (e.g.

Photodynamic effect of hypericin after topical application in the ex ovo quail chorioallantoic membrane model.

Photosensitizing properties of hypericin are well known, and the chicken chorioallantoic membrane has previously been used to test photodynamic effects of hypericin and other substances. In our study the photodynamic effect of hypericin in the ex ovo quail chorioallantoic membrane model was evaluated. Steady-state and time-resolved fluorescence spectroscopy of hypericin solution in PEG-400 and its mixture in PBS was performed to assess and characterize the process of aggregation and disaggregation of hypericin during the drug formulation preparation.

Kinetics and pharmacology of the D1- and D2-like dopamine receptors in Japanese quail brain.

Although the avian brain dopamine system and its functions have been studied much less than the mammalian one, there is an increasing interest in the role of dopamine and its receptors in a wide variety of motor, cognitive and emotional functions in birds with implications for basic research, medicine or agriculture. Pharmacological characterisation of the avian dopamine receptors has had little attention. In this paper we characterise the two classes of dopamine receptors in Japanese quail brain by radioligand binding techniques using [(3)H]SCH 23390 (D(1)) and [(3)H]spiperone (D(2)).

The effects of feed restriction on plasma biochemistry in growing meat type chickens (Gallus gallus).

The effect of feed restriction on plasma hormones (triiodothyronine - T(3), thyroxine - T(4), and corticosterone), protein, lipid, carbohydrate, and mineral metabolism and activity of plasma enzymes (creatine kinase, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase) were studied in meat type female chickens (Gallus gallus). Ad libitum fed birds were compared with those subjected to severe and moderate quantitative feed restriction from 16 to 100 days of age. Feed restriction elevated plasma T(4) and corticosterone levels and reduced T(3).

Chicks from a high and low feather pecking line of laying hens differ in apomorphine sensitivity.

Proactive rodents show a larger behavioral response to apomorphine (APO) than reactive copers, suggesting a more sensitive DA system in proactive individuals. Previously, chicks from a high feather pecking (HFP) and low feather pecking line (LFP) have been suggested to display a proactive and reactive coping strategy, respectively. Therefore, at approximately 4 weeks of age, the behavior of 48 LFP and 48 HFP chicks in response to an APO injection was studied using an open field.

Repeated apomorphine administration alters dopamine D1 and D2 receptor densities in pigeon basal telencephalon.

When pigeons are repeatedly administered a dose of apomorphine they show an increasing behavioral response, much as rodents do. In birds this expresses itself in an augmented pecking response. This sensitization is assumed to be largely due to a conditioning process.

Post-hatching dynamics of plasma biochemistry in free-living European starlings (Sturnus vulgaris).

This is the first study of plasma biochemical parameters in free-living altricial birds during an entire developmental period in a nest, represented by European starling (Sturnus vulgaris). Dynamics of postnatal changes from hatching until close to fledging (days 1 to 15) were registered. Parameters of protein metabolism represented by total proteins, albumin and globulin concentrations increased continuously during the observed developmental period.

Developmental changes in thyrotropic and somatotropic effect of TRH in precocial Japanese quail and altricial European starlings.

The thyrotropic and somatotropic effects of thyrotropin releasing hormone (TRH) in precocial Japanese quail (Coturnix japonica) and altricial European starlings (Sturnus vulgaris) during postnatal ontogeny were studied. Concentrations of thyroid hormones (TH) and growth hormone (GH) in the circulation were determined 60 min after the subcutaneous administration of TRH. In quail, TRH caused an increase of triiodothyronine (T(3)) in plasma during the phase of rapid growth, whereas thyroxine (T(4)) concentrations were not affected.

Influence of food restriction on dopamine receptor densities, catecholamine concentrations and dopamine turnover in chicken brain.

To investigate further a putative role of dopamine in control of food restriction-induced behavioural stereotypies, chickens were fed during rearing on either a daily restricted ration recommended by a breeding company, twice the recommended restricted ration, or ad libitum food. They were killed at 60 days of age and their excised brains were dissected into six regions and homogenized. Densities of dopamine D1 and D2 receptors were assessed, after first estimating binding parameters for [3H]SCH 23390 (D1) and [3H]spiperone (D2) in chicken brain homogenates.

Plasma thyroid hormone and growth hormone patterns in precocial Japanese quail and altricial European starlings during postnatal development.

Plasma concentrations of thyroid hormones (TH) and growth hormone (GH) during postnatal development in the precocial Japanese quail (Coturnix japonica), and the altricial European starling (Sturnus vulgaris) were measured. Developmental changes in plasma TH found in the starling, differ considerably from those detected in quail. In quail rather high triiodothyronine (T3) values were measured during the first few days after hatching.

Enhanced ornithine decarboxylase activity of chick muscle cells in culture by beta-adrenergic agonists.

The ability of beta-adrenergic agonists to stimulate ornithine decarboxylase activity (ODC) in chick muscle cell culture prepared from 11-day old embryos was evaluated. After 72 h of preincubation (myotube formation) the medium was supplemented for 4 h with noradrenaline, ritodrine, isoproterenol or clenbuterol, at concentrations of 10(-12), 10(-9) and 10(-6) mol/l. No significant response of ODC activity to noradrenaline was observed.

Effects of thyroid hormones on chick embryo muscle cell culture.

The importance of thyroid hormones (TH) in the normal development of muscles has been repeatedly postulated. The effects of physiological TH doses on ornithine decarboxylase (ODC) and protein synthesis in muscle cells have been studied using cell cultures prepared from 11-day-old chick embryos. Triiodothyronine nuclear receptors in primary muscle cell culture were characterized on the basis of the specific binding analysis as a single receptor class with the equilibrium dissociation constant Kd = 1.

Effects of exogenous melatonin on some endocrine, behavioural and metabolic parameters in Japanese quail Coturnix coturnix japonica.

1. Melatonin administration in drinking water (5 micrograms/ml) to Japanese quail resulted in a 20-fold increase of plasma melatonin levels in comparison with the control, day time concentration (0.34 +/- 0.

[Growth in broiler chickens after the regulation of sex differentiation using tamoxifen].

We studied the influence of an embryonal application of antiestrogen tamoxifen on gonad differentiation and sex dimorphism during the growth of Slovgal chickens. A single application of 500 micrograms tamoxifen to the incubated eggs before the onset of gonad differentiation induced in pullets the growth of the right gonad, which usually develops only in cockerels. Comparing the size of both gonads it is clear that the above dose of antiestrogen had the 22.

Effect of restraint upon hypothalamic and adrenal catecholamines in Japanese quail.

1. Changes in catecholamine concentration after periods of restraint up to 48 h in male Japanese quail have been measured. 2.

[Influence of hypokinesis on the physiological functions in fowl].

The authors examined in the submitted paper the effect of hypokinesis and post-incubation stress (which are characteristic for modern technologies of poultry cage keeping) on the endocrine functions, metabolic reactions, body weight growth and proteosynthesis in the muscle of cocks. The stress due to hypokinesis was observed in growing cocks housed in metallic cages in which they could hardly turn round. The findings obtained indicate that a 35-day hypokinesis did not exert any more significant influence both on physiological functions and body weight growth as well as on proteosynthesis in the muscle of cocks under study, however, it speeded up the protein metabolism in the muscle.