Stress-free blood sampling in minipigs: A novel method for assessing 24-h cortisol profiles and drug effects on diurnal and ultradian rhythms.

We developed a novel, stress-free blood sampling method for minipigs, allowing continuous cortisol monitoring over 24 h. Baseline cortisol levels exhibited both ultradian and diurnal rhythms. During nighttime, smaller ultradian rhythms overlaid a lower baseline cortisol, which increased in sleeping pigs before lights were turned on.

A systems pharmacokinetic/pharmacodynamic model for concizumab to explore the potential of anti-TFPI recycling antibodies.

Concizumab is a humanized monoclonal antibody in clinical investigation directed against membrane-bound and soluble tissue factor pathway inhibitor (mTFPI and sTFPI) for treatment of hemophilia. Concizumab displays a non-linear pharmacokinetic (PK) profile due to mTFPI-mediated endocytosis and necessitates a high dose and frequent dosing to suppress the abundant sTFPI, a negative regulator of coagulation. Recycling antibodies that can dissociate bound mTFPI/sTFPI in endosomes for degradation and rescue antibody from degradation have a potential in reducing the dose by extending antibody systemic persistence and sTFPI suppression.

Impact of capacity-limited binding on recombinant factor VIII and von Willebrand factor pharmacokinetics in hemophilia A rats.

Unlabelled: Essentials Knowledge of the interplay between FVIII and VWF pharmacokinetics (PK) is lacking. We characterized the capacity-limited PK of FVIII and VWF. The PK model described the PK of FVIII and VWF over a broad range of rFVIII doses.

A Minimal Physiologically Based Pharmacokinetic Model with a Nested Endosome Compartment for Novel Engineered Antibodies.

We proposed here a minimal physiologically based pharmacokinetic (mPBPK) model for a group of novel engineered antibodies in mice and humans. These antibodies are designed with altered binding properties of their Fc domain with neonatal Fc receptor (FcRn) or the Fab domain with their cognate targets (recycling antibodies) in acidic endosomes. To enable simulations of such binding features in the change of antibody pharmacokinetics and its target suppression, we nested an endothelial endosome compartment in parallel with plasma compartment based on our previously established mPBPK model.

The pan-Kv7 (KCNQ) Channel Opener Retigabine Inhibits Striatal Excitability by Direct Action on Striatal Neurons In Vivo.

Central Kv7 (KCNQ) channels are voltage-dependent potassium channels composed of different combinations of four Kv7 subunits, being differently expressed in the brain. Notably, striatal dopaminergic neurotransmission is strongly suppressed by systemic administration of the pan-Kv7 channel opener retigabine. The effect of retigabine likely involves the inhibition of the activity in mesencephalic dopaminergic neurons projecting to the striatum, but whether Kv7 channels expressed in the striatum may also play a role is not resolved.

NS19504: a novel BK channel activator with relaxing effect on bladder smooth muscle spontaneous phasic contractions.

Large-conductance Ca(2+)-activated K(+) channels (BK, KCa1.1, MaxiK) are important regulators of urinary bladder function and may be an attractive therapeutic target in bladder disorders. In this study, we established a high-throughput fluorometric imaging plate reader-based screening assay for BK channel activators and identified a small-molecule positive modulator, NS19504 (5-[(4-bromophenyl)methyl]-1,3-thiazol-2-amine), which activated the BK channel with an EC50 value of 11.

A novel B-domain O-glycoPEGylated FVIII (N8-GP) demonstrates full efficacy and prolonged effect in hemophilic mice models.

Frequent infusions of intravenous factor VIII (FVIII) are required to prevent bleeding associated with hemophilia A. To reduce the treatment burden, recombinant FVIII with a longer half-life was developed without changing the protein structure. FVIII-polyethylene glycol (PEG) conjugates were prepared using an enzymatic process coupling PEG (ranging from 10 to 80 kDa) selectively to a unique O-linked glycan in the FVIII B-domain.

Selective positive modulator of calcium-activated potassium channels exerts beneficial effects in a mouse model of spinocerebellar ataxia type 2.

Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disorder caused by a polyglutamine expansion within the Ataxin-2 (Atxn2) protein. Purkinje cells (PC) of the cerebellum fire irregularly and eventually die in SCA2. We show here that the type 2 small conductance calcium-activated potassium channel (SK2) play a key role in control of normal PC activity.

Kv 7 positive modulators reduce detrusor overactivity and increase bladder capacity in rats.

The effects of the Kv 7 channel modulators retigabine (opener) and XE991 (blocker) on rat bladder function were investigated ex vivo and in vivo to assess the potential of Kv 7 openers for the treatment of overactive bladder. In organ bath studies, capsaicin-stimulated rat urinary bladder rings were exposed to retigabine and XE991 and the effect on tension and amplitude was evaluated. In anaesthetized rats, retigabine (0.

Effect of the SK/IK channel modulator 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591) on contractile force in rat, pig and human detrusor smooth muscle.

Objective: • To investigate the importance of small (SK)- and intermediate (IK)-conductance Ca2(+) -activated K(+) channels on bladder function, by studying the effects of 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591), a new modulator of SK/IK channels, on contractions induced by electrical field stimulation (EFS) and carbachol in rat, pig and human detrusor.

Patients And Methods: • Detrusor biopsies were obtained from rats, pigs and male patients undergoing cystectomy because of bladder cancer. • Force was recorded using myographs.

Functional effects of the KCNQ modulators retigabine and XE991 in the rat urinary bladder.

The anticonvulsant retigabine has previously been reported to inhibit bladder overactivity in rats in vivo but the mechanism and site of action are not known. In the present study we investigated the effect of retigabine in isolated rat bladder tissue. Bladders from Sprague-Dawley rats were cut transversally into rings and mounted on an isometric myograph.

The importance of genetic background on pain behaviours and pharmacological sensitivity in the rat spared serve injury model of peripheral neuropathic pain.

Neuropathic pain conditions can encompass a diverse constellation of signs and symptoms consisting of sensory deficits, allodynia and hyperalgesia. Animal models of neuropathic pain have enabled the identification of key pathophysiological changes occurring within nociceptive pathways as a result of injury, and serve an invaluable role for preclinical screening of novel analgesic candidates. We have produced the first systematic description of the development and maintenance, and the pharmacological sensitivity of nociceptive behaviours in four rat strains with different genetic background (outbred Sprague-Dawley and inbred Brown Norway, Lewis and Fischer 344 rats), using the spared nerve injury model of peripheral neuropathic pain.

Venlafaxine compromises the antinociceptive actions of gabapentin in rat models of neuropathic and persistent pain.

Rationale: Neuropathic pain is associated with a number of disease states of diverse aetiology that can share common pathophysiological mechanisms. Antiepileptic drugs modulate ion channel function and antidepressants increase extracellular monoamine levels, and both drug classes variously attenuate signs and symptoms of neuropathic pain. Thus, coadministration of the antiepileptic gabapentin and the antidepressant venlafaxine may provide superior pain relief to administration of either drug alone.

Centrally-mediated antinociceptive actions of GABA(A) receptor agonists in the rat spared nerve injury model of neuropathic pain.

Gamma aminobutyric acid (GABA) plays a major role in the central hyperexcitabilty associated with nerve damage. The precise antinociceptive actions mediated by GABA(A) receptor agonists remain unclear as previous studies have shown mixed results in neuropathic pain models. Thus, various drugs which modulate GABA(A) receptor function were tested in the rat spared nerve injury (SNI) model of neuropathic pain.